For 60 years the two letters "SL" have had a mystical resonance among  automotive enthusiasts. They stand for powerful sportiness, exciting  design, effortlessly superior style, technical innovations and the  ultimate in engineering artistry. The Mercedes-Benz SL-Class inherited  these genes from its forefather, designed as a racing car. In 1952 it  came to the international race tracks, saw and conquered. It was from  this car that Mercedes-Benz derived the first series-production model in  1954, the legendary 300 SL gullwing.  And ever since, Mercedes-Benz has been setting the bar high in the  luxury sports car segment with the SL over five model generations.
The  unique combination of systematic sportiness, refined luxury and yet  unrestricted suitability for everyday use at the same time is what makes  the Mercedes-Benz SL-Class the dream car it is - and it is also what  lies behind its success where sales are concerned. The SL was always  ahead of its time technically - even when it was rolling off the  production line for 18 years at a time, as was the case with the SL  bearing the internal code R107 (from  1971 to 1989). Over 650,000 SL vehicles have left the production halls  in Sindelfingen and Bremen since 1954, and from the last model  generation alone - which celebrated its premiere in 2001 - nearly  170,000 specimens found their way into the hearts of the enthusiasts  amongst fans of high-calibre sports cars.
The new generation of the Mercedes-Benz SL-Class now being presented  is the sixth to follow the 1952 racing car. In the unique tradition of  the SL it is entering its era as an athlete, refined aesthete and  innovative trendsetter with an extraordinarily high utility value.  Mercedes-Benz is initially offering the new SL with two engines - as the  SL350 with a V6 engine and as the SL500 with a V8. The new BlueDIRECT  engines have an output of 225 kW (306 hp) in the SL350 and 320 kW (435  hp) in the SL500 (a 12-percent increase over the predecessor).
Moreover,  the new Mercedes-Benz SL-Class breathes new life into the meaning of  the famous abbreviation "SL" - super-light - through systematic weight  reduction. For the first time ever, Mercedes-Benz is implementing an  all-aluminium bodyshell in series production. The newly developed  vehicle weights approximately 110 kilograms less than a comparable  bodyshell made of sheet steel. Nevertheless it is even more rigid - and  safer - than its predecessor.  Mercedes-Benz has achieved this through a systematic intelligent  material mix of aluminium alloys and aluminium components which are  tailor-made for the respective requirements, combined with just a few  portions of high-strength steel and magnesium.
Although the new SL  is even more comfortable and has more safety devices on board than its  predecessor and therefore does actually sacrifice some of the weight  saved through the aluminium bodyshell, the scales show some astonishing  figures: the new SL500 (1785 kg) weighs around 125 kilograms less than  its predecessor. On balance, the SL350 (1685 kg) is even 140 kilograms  lighter - all thanks to a host of other intelligent enhanced details to  reduce weight, which Mercedes-Benz has also implemented in the new SL in  addition to the aluminium bodyshell.
And these measurement  results do not just impress as figures on the page; they are very much  perceptible and tangible in practice, too. The resulting increase in  longitudinal and lateral dynamics facilitates superb performance with a  decided passion for cornering. The greater track width at both the front  (+ 38 mm) and rear (+ 77 mm) axle serves the handling which is at once  sporty and agile and keeps the car under safe control. Drivers will find  the new Mercedes-Benz SL-Class even more agile than its predecessor -  sheer pleasure for those of a sporty orientation.
There are two  suspension variants from which to choose. The SL is supplied as standard  with semi-active adjustable damping (lowered by ten millimetres in the  AMG sports package). The active suspension system ABC (Active Body  Control) is available as an optional extra. Unique the world over, it  has been enhanced especially for the new SL.
In keeping with the  Mercedes-Benz tradition, the new SL couples its sharpened athletic  profile and agile nimbleness with a luxurious ambience. Its high-quality  equipment and appointments contribute to the exquisite motoring  pleasure that can be experienced every kilometre of the way. Fine  materials, finished with great attention to detail, shape its style and  character. The levels of comfort here - unique in the segment of luxury  sports cars - blend with high everyday practicality, for the new SL  shines with top marks where open-top motoring, suspension comfort and  comfort on long journeys are
concerned - plus its exemplarily low  background noise, which is comparable with that of a saloon. This all  adds up to the fact that this vehicle is a Gran Turismo in the very best  sense of the word.
The safest and the most sparing
Thanks  to the crash-optimised aluminium structure, standard-fit PRE-SAFE® and  assistance systems on the same high level as the S-Class, the SL is the  world's safest roadster.
What's more, it is the most frugal one in  its class. The SL350 consumes 6.9 litres over 100 kilometres, which is  virtually 30 percent less than its predecessor (CO2 159 g/km). The  SL500, too, posts a persuasive set of efficiency figures: 9.1 litres per  100 kilometres (minus 22%) correspond to 212g/km CO2.
The design,  meanwhile, displays all the classic proportions so characteristic of  the SL. Right from the first glance the masculine-looking roadster with a  broad tail end is immediately identifiable as a member of the current  family of sports cars from Mercedes-Benz. It emphasises its autonomy  through a multitude of details created with loving care.
The sixth  generation of the Mercedes-Benz SL-Class also offers a vario-roof that  can be retracted into the boot using an electrohydraulic mechanism to  save space, converting the SL into a roadster or a coupé, depending on  the driver's wishes and the weather. Unlike its predecessor, three  versions are available for the new SL: painted, with a glass roof or  with the unique panoramic vario-roof featuring MAGIC SKY CONTROL. The  transparent roof switches to light or dark at the push of a button. When  light it is virtually transparent, offering an open-air experience even  in cold weather. In its dark state the roof provides welcome shade and  prevents the interior from heating up in bright sunlight.
With two  innovations, the new SL remains true to its tradition as technological  trendsetter:
- MAGIC VISION CONTROL is a new intelligent, high-efficiency windscreen wiper/washer system. Its system of channels supplies water to the windscreen just in front of the laser-cut wiper blade lip. As a result, when spraying, there are no gushes of water on the windscreen to disrupt visibility, and yet the windscreen is kept clean.
- Also unique, the Frontbass system uses the free spaces in the aluminium structures in front of the footwell for housing the bass loudspeakers. As a result, the new SL features clear, crisp bass sounds that facilitate a concert hall ambience even with the top down.
Both  innovations are part of the extensive standard equipment of the new SL.
Design:  Masculine, muscular athlete's physique
The design of  every Mercedes-Benz SL has an obligation to a great legend, and yet it  is always very clearly looking to the future. The designers have  unmistakably showcased the youngest generation of the style-defining  roadster on the basis of tradition, but also with new perspectives and  visions. This has resulted in a formal identity and the high overall  aesthetic quality.
In the interplay between innovation and  tradition we have created a stylish, sporty and elegant luxury sports  car with the classic, well-balanced hallmark SL proportions: the long  bonnet is followed by a compact, set-back passenger compartment. A  broad, muscular, racy-looking tail end completes the picture.
Design  boss Professor Gorden Wagener: "The athletic, sports star's physique  with its masculine, muscular character says a great deal about the new  SL and confidently emphasises its status as the high-performance heart  of our brand. At the same time, discerning athletic standards are met by  powerfully sculpted surfaces formed by just a few lines and beautifully  crafted details. The traditional design elements from our rich history  are more than visual quotations. They tell of the courage and the  pioneering spirit which have shaped our brand, and reflect these  properties in a contemporary way - with enthusiasm and passion.  Alongside top technical performance and innovations, it is also this  which makes the new SL an unmistakable character."
The  front signals a self-confident presence
Visually, the new  SL is clearly marked out as a prestigious member of the current  Mercedes-Benz sports car family. At first glance this is evident from  the very upright classic sports car radiator grille which has featured  on all the Mercedes-Benz vehicles with a sporty character - right from  the initial generation of the SL. The central star in the radiator  grille points the way to the future: it is a contemporary  reinterpretation of the famous trademark, which now runs into the  centrepiece with organically flowing contours.
What's  more, on the new roadster the designers have waived the classic 
separation  of the bumper and the radiator grille. The lower edge of the grille now  dips into the bumper, supporting the pronounced V-shape and resulting  in more formal presence. In addition to this, the steeply positioned  radiator grille lengthens the bonnet in visual terms. Two air outlet  grilles, each with two chromed fins, have their roots in Mercedes-Benz's  traditional, dynamic design repertoire. A succinctly sculptured edge -  developing from the upright radiator grille - draws across the long  bonnet in a taut arch and flows organically into the A-pillar.
Dynamically  positioned at an angle, headlamps located far on the outside flank the  distinctive front and the broad air intake, giving the new roadster its  own inimitable look. It appears masculine and it does also radiate a  certain restrained aggressiveness.
The standard-specification ILS  headlamps are characterised by very high-quality tubes for the low and  main beam which have been styled with great attention to detail, plus a  chrome bracket surrounding the main headlamp and the flared arrangement  of the indicator lamps and sidelights. All the further functions feature  LED technology - such as the distinctively curved sidelights and the  horizontal band of the daytime running lamps in the outer sections of  the bumper.
The silhouette displays muscles with character
A  minimal amount of artistically styled lines define the athletic yet  smooth surfaces of the flanks. The shoulderline rises from the headlamps  and stretches like a tensed muscle over the entire length of the  vehicle and into the tail lights. Side grilles with fins in the front  wings stylishly cite the classic SL legend and form the starting point  for a feature line. This structures the proportions and lends the  vehicle a visual forwards thrust even at a standstill. It tapers out in  the tail light as a discreet line.
Free-standing exterior mirrors  located on the beltline not only support the modern character of the  side view; thanks to this position they also improve vision of the road.
Depending  on the engine variant, various light-alloy wheels are available in  17-inch and 18-inch versions. The exquisitely bordered wheel arches are  designed for a maximum size of 19 inches at the front and 20 inches  (only in the case of AMG) at the rear.
Muscular tail end
A  small number of sweeping lines shape the broad, clearly defined tail  end. Elegantly flowing and at the same time racy and muscular, it forms  the roadster's distinguished finishing flourish that is so full of  character. Thanks to the boot lid with its steel interior and plastic  panelling, it has been possible to stow the aerials out of sight inside  the vehicle so that they do not interrupt the flowing lines in the rear  area. This is also the case with the roll-over protection, which lies  hidden from view in the body and is only activated in case of danger.
Tail  lights with LED High Performance technology highlight the width of the  tail end. They taper inwards to a point and have a discreet kink in the  contour. The rear fog lamp is located centrally between two trapezoidal  exhaust tailpipes. A horizontal swage line in the lower area of the  bumper provides added emphasis of the broad effect.
The colour  range for the exterior encompasses twelve different paints. These  include the BRIGHT paint diamond white and the special colour cerussite  grey metallic SHAPE - the first matt paint in the standard-specification  paint range for a Mercedes-Benz model series.
Interior  and appointments: Luxurious comfort and sporty precision
The  interior of the new SL impresses with its generous amount of space,  high-quality materials, high sense of perceived value and lovingly  crafted details displaying tangible and visible precision.
Compared  with its predecessor, the new generation of the SL is much longer (+ 50  mm to 4612 mm) and wider (+ 57 mm to 1877 mm), providing more room for  more comfort in the interior, too. Shoulder room (+ 37 mm) and elbow  room (+ 28 mm) have been increased, exceeding the dimensions normally  found in this vehicle class. Clear lines create a formally coherent  internal space within this comfortable interior. Perfectly in tune with  the roadster's character, it combines the unpretentious atmosphere of a  high-performance sports car with the comfortable, stylish ambience you  come to expect in a luxurious touring car.
The wrap-around  effect has class
In conjunction with the beltlines on  the doors and the parcel shelf, the upper section of the dashboard  creates a formal unity and - with the exception of the black interior -  it is always styled in a contrasting colour. Generously used wood trim  extends from the centre console across the dashboard into the doors,  creating a pleasant wrap-around effect. Three types of wood along with  two different aluminium trim finishes are available (high-gloss brown  walnut, satin-finish light brown poplar, high-gloss black ash), plus two  differently treated longitudinal-grain aluminium trim parts (light or  dark). The links between the dashboard, centre console and door trim  panels have been styled so that they are continuous and they support the  wrap-around effect. Minimal gap dimensions please the eye and represent  the high precision with which the SL is manufactured.
High-quality  instruments add emotionally appealing flourishes
In the  area of the dashboard, four circular ventilation outlets provide some  striking eye-catching touches. Set in metal, these air vents are  reminiscent of jet engines and are a contemporary, emotively interpreted  way of paying homage to the history of Mercedes-Benz sports cars.
Inside  two tubes the sporty instrument cluster boasts classic round dials with  three-dimensional graduated rings, back-lit dials in the centre of the  tachograph and rev counter, plus high-quality needles. In the centre  between the two round dials, a colour display provides information from  the on-board computer and indicates vehicle functions. The system is  operated via a three-spoke sports steering wheel with shift paddles and  twelve function buttons. The steering wheel featuring a flattened bottom  section has an ergonomic grip area and galvanised spokes, and is  covered with nappa leather - in the airbag section, too.
A large  COMAND colour display in the centre of the vehicle takes care of the  numerous display functions for the entertainment, communication and  navigation facilities. A particularly eye-catching feature on the tunnel  of the centre console is a new DIRECT SELECT shift lever. Small and  fine, it is a true visual highlight. Like the central rotary knob for  operating the COMAND system, it is optimally positioned from an  ergonomic point of view. Located in front of these controls is the  lidded compartment for the two cup holders.
Spotlight on  the stylish ambience
Making dynamism visible is what it's  all about where the ambient lighting in the SL is concerned. The  fibre-optic cables with three colour options to choose from stretch  between the beltline and the door centre panel in one tier over  virtually the entire length of the door, behind the trim on the  dashboard and in the front panelling.
Seats with a noble,  sporty character
The new Mercedes-Benz SL-Class's fully  electric seats with a memory function meet discerning and wide-ranging  standards regarding seating comfort, ergonomics, safety and sportiness.  The ergonomically optimised seats themselves are more slender than in  the predecessor and emphasise the noble, sporty character. This is  underlined in visual terms by sophisticated stitched seams and by a  layout which varies depending on the choice of leather. Alongside  excellent lateral support, the seats also offer high levels of comfort.
The  superstructure of the seat cushion and backrest is formed by a  weight-optimised welded construction of steel and sheet metal panel  parts. This structure also makes a significant contribution towards  transverse support for the sidewall in the event of a lateral collision.  In addition, a thorax-sidebag is installed in the backrest. A newly  developed combination of a sine spring core principle with rubberised  matting and a foam layer as damping ensures support and comfort.
Both  the driver and the passenger can adjust their seats precisely according  to their requirements and body measurements. Even in the standard  equipment there are extensive electrical adjustment options available  for doing so, enabling fore-and-aft and height adjustment to be made  just as easily as the seat cushion angle, cushion depth and backrest  angle adjustment. The crash-responsive head restraints are also  adjustable for height. The range of equipment also includes 4-way lumbar  support adjustment - this feature is housed in the centre section of  the backrest cover. The occupants can operate it via the central control  panel and the head unit. Using the memory buttons, the current seat  position can be stored, and on the driver's side this also applies to  the positions of the steering wheel and exterior mirror.
A very  attractive solution has been found for convenient access to the rear  compartment for easy loading - in both visual and functional terms. A  button on the shoulder of the backrest operates the backrest lock  electrically and enables the seats to be moved forwards and backwards in  order to create sufficient room to manoeuvre.
Also part of the  standard specification is a seat occupancy sensor with automatic child  seat recognition on the front-passenger side - for child seats with a  transponder specially approved for Mercedes-Benz.
For enhancing  comfort even further, in the case of the leather appointments the seats  are covered with sun-reflecting leather. This specially coated leather  reflects the heat of the sun and, in particular where the appointments  colours are dark, it reduces the extent to which the surface heats up.  In combination with the optional active ventilation the thermal seat  comfort is tangibly improved.
The following seat variants can be  selected as an optional extra:
- Luxury heated seats with active seat ventilation: it ensures a pleasant seating climate. Leather appointments are a prerequisite for this option
- Active multicontour seat package: three air chambers in the lumbar area can vary the contour of the seats in order to prevent fatigue. Elongated air chambers in both of the side cushions on the backrest ensure optimum lateral support
- Dynamic multicontour seat: the dynamic multicontour seat is an enhanced version of the multicontour seat. It automatically adjusts the lateral structure of the backrest in accordance with the current driving situation. In order to do this it varies the air pressure in the seat bolsters on the backrest electropneumatically, depending on the steering angle, lateral acceleration and speed
Health and comfort-conscious  climate
The control panel for the standard-specification  luxury automatic climate control THERMOTRONIC featuring separate  temperature adjustment for the driver and passenger has been redesigned  and revised. Mercedes-Benz has placed particular emphasis on new  technologies for saving energy. They include a window demisting sensor  integrated in the base of the interior mirror. It measures the window  temperature and interior humidity and transmits these data to the  climate electronics. They can use them to determine whether the  windscreen has misted up. If this is not the case, in A/C operation it  can continuously adjust the compressor in the background if no  dehumidification is necessary. In other words: thanks to the sensor, the  compressor can be operated as required, saving drive energy. The A/C  function can remain permanently active. A further advantage is that, as  the air conditioning only dehumidifies and cools as much air as  necessary, dry eyes are prevented - a tangible gain in terms of comfort.
The  air conditioning is also linked to the ECO start/stop function and can  therefore also regulate the climate during the stop phases.
So  that SL drivers can enjoy an open-air experience even when the weather  is cool, the innovative neck-level heating system AIRSCARF is available  as an optional extra - as was the case with the predecessor. Warm air  flows through a nozzle at the front of the head restraints, and the  system directs it around the head and neck area of the occupants.
Room  for luggage and lots of equipment
Suitability for  everyday use is a key word which is traditionally taken extremely  seriously at Mercedes-Benz - even in the case of vehicles designed to be  very sporty. This is why the occupants in the new SL will find plenty  of stowage facilities for larger and smaller items alike. In addition to  the glove compartment, the centre console offers three stowage  compartments within easy reach:
- One of these is at the front beneath the air-conditioning control panel, which can be optionally fitted with two cup holders or with an ashtray and one cup holder
- A large stowage compartment beneath the armrest can be used for the safe storage of a telephone, iPod ® or similar, for example
- A centrally located rear box with a retractable luggage cover completes the range. A bottle holder is fitted here as part of the standard specification, whilst a fire extinguisher is available as an optional extra
A lockable rear box behind the driver's seat creates  additional stowage space. Its catch is automatically closed when the  vehicle is locked.
In the lower section of the door trim, a long,  open door pocket offers further, easily accessible stowage space. As no  bass loudspeakers have to be fitted in the door thanks to the Frontbass  system, Mercedes-Benz makes sensible use of the space gained here by  adding an extra stowage compartment, which can be used for an umbrella,  for instance.
The designers have also thought the details through:  smaller but useful items can be fixed in place by a net on the centre  tunnel of the passenger's footwell.
The design of the boot is  largely determined by the vario-roof, which has to be housed in the  upper part of the boot when the roof is open. In total the new SL offers  luggage capacity of up to 504 litres - 364 litres with the roof stowed.  There is always room for stowing luggage or two golf bags without any  problems at all, thanks to the optimised boot design.
A luggage  cover which can be adjusted lengthwise with a handle prevents pieces of  luggage from colliding with roof elements in the boot when opening the  roof. Only when the cover is adjusted to the rear can the vario-roof be  opened. Anyone wanting to use the entire boot capacity when the roof is  closed can adjust the cover to the front or remove it completely.
At  the press of a button, the roof elements stowed in the boot can be  tilted upwards by about 25 degrees to make loading and unloading easier -  as was the case in the predecessor (Easy-Pack system).
The  compressor and the TIREFIT filler bottle are housed in a stowage  compartment in front of the recess which can be accessed by lifting up  the boot floor.
HANDS-FREE ACCESS - 'kick' to open
One  of the new products and features from Mercedes-Benz is a system known  as HANDS-FREE ACCESS, which is included in the KEYLESS-GO package. It is  available on request for the new SL for the first time anywhere in the  world, and it allows drivers to operate the boot lid without using their  hands. This work is taken care of by a hydraulic drive system, for  which the control signals are given by the SL owner without touching  anything, but by making as though to kick the area of the rear bumper  with their foot; doing so activates this fully automatic  comfort-increasing equipment. Mercedes-Benz is the only manufacturer to  offer a system which not only opens but also closes the boot lid  automatically.
With the innovative convenience function HANDS-FREE  ACCESS there is no longer any need for drivers to have to get annoyed  by having to put their purchases and other objects down on the - often  dirty - ground when out shopping and when they literally have their  hands full, in order to reach for the handle. Should an unintentional  'kick' result in the boot lid opening or closing without the driver  wanting this to happen, a second kick will correct it. When this occurs,  the automatic system interrupts the procedure and reverses the effect  of the signal given in error by actuating the boot lid against the  original direction of movement - in the case of unintended opening, the  second kick closes the boot lid again.
An appropriate safety  program facilitates unhindered use of the HANDS-FREE ACCESS system. An  acoustic signal provides the information that an opening or closing  procedure has been initiated, and an automatic reversing function stops  the boot lid as soon as the system recognises that there is an obstacle  blocking the boot lid.
For the HANDS-FREE ACCESS system to be  included, the vehicle must be fitted with KEYLESS-GO - this allows  non-contact access to the vehicle In addition to this the correct  KEYLESS-GO vehicle key has to be in the vicinity of the vehicle, so in  order to open the doors it can, for example, stay in the driver's coat  pocket or handbag. In order to activate the HANDS-FREE ACCESS system for  the boot lid, the KEYLESS-GO key must not be further than 1.5 metres  away from the rear end of the vehicle.
Body and bodyshell:  Aluminium comes up trumps
Cars are becoming increasingly  safer, more comfortable, but often heavier as well. The new  Mercedes-Benz SL not only stops this trend, it turns it around. In spite  of increased comfort, performance and safety, it is 140 kilograms  lighter than its predecessor.
The greater part of the  weight-reduction "diet" is hidden from the eyes of the observer of the  SL. Under the aluminium outer skin there is a bodyshell made almost  entirely from aluminium, only very few components being made from other  materials. The even lighter magnesium is used in part for the cover  behind the tank. The A-pillars and the roof frame are of steel sheet  metal incorporating high-strength steel tubing. For these elements steel  is the best solution to provide survival space for occupants in the  event of the vehicle overturning.
The bodyshell of the  Mercedes-Benz SL-Class is the first all-aluminium bodyshell to be  produced in large series at Mercedes-Benz. This entirely new development  weighs 254 kilograms and is thus 110 kilograms lighter than a  comparable steel bodyshell. Further extensive lightweight design  features compensate the additional weight unavoidably caused by the  increased comfort, the new assistance systems and other technical  features. Under the bottom line an enormous weight advantage remains for  the new SL. As the SL500 it weighs 125 kilograms less than its  predecessor, while the SL350 weighs 140 kilograms less than its previous  version. And its preceding model already had a lightweight aluminium  bonnet and doors.
"The effect is rather as if a heavyweight-class  passenger had got out of the car and taken their heavy flight luggage,  too" says Dr Thomas Rudlaff, responsible for the aluminium bodyshell at  Mercedes-Benz. "The result is perceptible and measurable. Less weight  means more dynamism and less consumption. In other words: the motoring  enjoyment increases and the environmental burden decreases."
For  the roadster the aluminium bodyshell is superior to a steel  construction
The developers at Mercedes-Benz did not rest  content achieving weight benefits alone. The aluminium structure had to  be superior to a steel construction in terms of rigidity and comfort as  well. In order to attain this high objective, developers consistently  went for an intelligent lightweight construction, and explored many new  paths to do this. Every single component of the aluminium bodyshell was  specifically optimised for its particular function and expected loads.  Thus, diverse processes are used to make different kinds of aluminium  depending on the use the component is to be given: the parts are made by  chill casting or vacuum die casting, worked into extruded aluminium  sections or into aluminium plates of thicknesses that vary within one  and the same component; these are what are known as the tailored welded  blanks. Expressed in numbers, the bodyshell weight is made up of: 44  percent cast aluminium, 17 percent aluminium sections, 28 percent  aluminium sheet metal, 8 percent steel and 3 percent of other materials.
At  the Bremen production facilities the parts are assembled using diverse  load-adequate joining methods, some of which are innovative processes.  Secure joints are ensured, for example, by MIG welding, hemming,  bonding, self-piercing rivets, flow hole bolting, or friction stir  welding - a joining method by which a highly resistant weld seam is  produced by means of friction heat; a method particularly well-suited to  aluminium on account of its low melting point.
Particular  highlights of the bodyshell:
- The firewall is at present the largest aluminium cast component made in large series for vehicle bodywork
- Many sheet metal parts are designed in such a way that for the first time they can be made from 100-percent recycled aluminium, saving 80 percent of the energy used in their production.
- The main floorpan consists of a 3-layer shaped panel made from thin, extrusion-moulded hollow sections, welded together by friction stir welding.
- The longitudinal members in the vehicle front end are made using high-pressure hydroforming (IHU) technology, which enables the creation of highly complex and robust components, permitting optimum use of reduced installation spaces.
- The door sills (longitudinal members) consist of 1.7 metre-long, 7-chamber extrusion-moulded aluminium sections; these provide rigidity in the lateral sectors and safety in the event of a collision. Flexible chamber distribution makes possible a minimum component weight coupled with optimum characteristics.
- The tunnel is made of aluminium sheet metal with a reinforcement of varying thickness (3 different thicknesses depending on the sector, a so-called tailored welded blank, TWB).
- The rear sector floor is a MIG welded frame with a hollow chilled cast longitudinal member as its central element. This technique is employed in the SL for the very first time in automotive bodyshell construction.
- The rear sector floor frame structure is closed by floor sheet metal panels and the boot tub made by vacuum die-casting.
- The boot recess is made from recycled sheet metal.
- The central member connects the front end with the rear sector floor. The mounting points for the drive shaft, the transmission cross beam, the transmission tunnel braces and the seat bolting points on the tunnel side are all integrated into a single element. The wall thicknesses and rib distribution are oriented bionically towards the requirements and loads.
- Many other components were optimised bionically, i.e. based on examples from the natural environment. These structures reduce the vehicle weight compared to a classic design even further.
The sum total of all the  design measures leads to a lightweight, torsionally and flexurally rigid  bodyshell with an optimum rigidity/weight ratio. It was possible to  increase the bodywork's torsional rigidity by more than 20 percent over  the already highly rigid preceding model series. This is confirmed by  measurements of the new SL's torsional strength - at 19400 Nm per degree  the roadster achieves an absolute top value (its predecessor already  reached 16400 Nm per degree).
Meets the highest safety  standards
At the same time the high-strength structural  elements of the aluminium bodyshell make the new SL even safer than the  preceding model in the event of a collision. Extrusion-moulded sections,  connecting cast nodes and a double-thickness plate floor form a  passenger compartment that is just as lightweight as it is sturdy. Two  aluminium sections in each door together with the side sills (very rigid  thanks to their internal chamber structure) and crash-resistant seats  provide the greatest possible survival space in the event of a side  collision.
A front end deformation zone acting on several levels  and in which the aluminium front axle subframe is integrated as an  additional third longitudinal member, distributes collision forces to a  large area, conducting them past the passenger compartment. And in the  rear, too, there is sufficient energy-absorbing deformation potential. A  structural cage made from chilled cast longitudinal members,  transversal sections and a cast magnesium tank separation bulkhead also  contribute to this. This is also where the fuel tank is nested in a  crash-protected manner above the rear axle. This way all the
statutory  safety requirements are met as well as the even stricter ones from  Mercedes-Benz.
Best marks for NVH comfort
Thanks  to its innovative aluminium bodyshell concept, the new SL is also  unique among the roadsters in terms of NVH comfort (noise, vibration,  harshness). One contributing factor towards its optimum vibration and  road roar characteristics is a very rigid connection between the front  section and rear floor, allowing relaxing travel even over long  distances, and at the same time offering impressive driving dynamics.
Although  aluminium features a higher sound emission and radiation level than  steel, the new SL is the quietest vehicle in its class. Mercedes-Benz  compensates for the acoustic disadvantages of aluminium by means of a  consistent sound insulation concept with targeted adaptation of the  sound damping materials to each problem zone, and through the use of  innovative sound-insulation materials:
- A special firewall damping with variable mass distribution and a significant heavy layer proportion attenuates engine noise.
- In conjunction with the plate floor, single-piece, foam-backed carpeting with virtually no seams reduces the roll noise of the vehicle in the interior.
- A spray-on lining attenuates the structure-borne sound in the vehicle interior and exterior.
- Textile wheel arch linings, acoustically absorbing shield plates and bodyshell foam elements for critical sectors also contribute towards a smooth ride.
- Damping in the rear wall transversal cross member and boot lateral elements as well as in the forced ventilation openings prevent disruptive tyre and wind noises from making themselves unpleasantly noticeable in the vehicle interior.
A  further contribution to the good interior acoustics is the laminated  glass windscreen with acoustic film. The transparent, highly resilient  film absorbs the vibrations of the windscreen and reduces the  perceptible sound level in many frequency ranges.
The precision  workmanship on the acoustics goes so far as to ensure that the hydraulic  pump for the electrohydraulic vario-roof is encapsulated and decoupled  from the bodyshell. In addition to this, a newly developed insert nozzle  sees to it that the pressure pulsation in the pump is reduced to a  minimum right from the outset. This means that pump noises are only  barely audible for the driver and passenger.
The doors and  the bonnet, too, are lightweight
The intelligent  material mix is completed by the boot lid, of SMC-hybrid design (SMC =  sheet moulding compound). It consists of a single-shell synthetic  material panel mounted on a steel reinforcement. Both materials have  virtually identical thermal expansion coefficients and complement each  other very well. The interior steel construction permits maximum  rigidity with minimum use of space, while the plastic panelling allows  the full integration of the aerials for navigation, digital radio and  mobile telephony out of sight in the rear area so that the SL does not  need to carry a bothersome aerial stump on its aerodynamically refined  body.
The bonnet of the SL is made from aluminium, as was that of  its predecessor. It was optimised in terms of form and materials,  contributing towards the outstanding pedestrian protection.
The  doors, too, are of a lightweight design and made from aluminium. They  are fashioned from a combination of sheet metal, extruded sections and  cast metal parts, joined by diverse methods: riveting, bonding and  hemming. Their aluminium and steel hinges are friction-based and are  infinitely adjustable to any desired angle when opened, so that when  getting into or out of the car they can remain securely open at any  angle permitted by the space available at the side. This is particularly  desirable in cramped parking conditions such as in a garage or car  park.
Unique item of equipment: MAGIC SKY CONTROL
The  proven electrohydraulic vario-roof - which turns the roadster into a  closed coupé with a fixed roof in just a few seconds at the push of a  button - has been intelligently enhanced, with Mercedes-Benz continuing  to play the pioneering role here. For the new SL Mercedes-Benz is for  the very first time offering drivers the choice between three variants  of the lightweight-construction vario-roof:
- The base version is a roof painted in the vehicle colour
- As an alternative, a transparent variant with a roller blind can be selected
- The third variant from which drivers can choose is the panoramic vario-roof with MAGIC SKY CONTROL. This glass roof switches to light or dark as required at the press of a button. When light it is virtually transparent, offering an open-air experience even in cold weather. In its dark state the roof provides welcome shade and prevents the interior from heating up when the sun's rays are very intense. In other words: a feel-good atmosphere at the touch of a button
The operating  principle is based on the physics of a plate condenser: if the glass  structure is subjected to an electrical voltage, particles in the  structure position themselves so that light is able to pass through the  glass. If the voltage remains switched off, however, the particles  position themselves randomly. This partially blocks the light, and the  glass remains dark. The control unit and converter are integrated into  the front section of the roof, and the switch is in the overhead control  console.
In addition to the unique panoramic effect and  transparency at the touch of a button, MAGIC SKY CONTROL also provides  an atmosphere of wellbeing. UV and infrared light are also effectively  blocked in transparent mode, while insulation increases even more  significantly in the darkened mode, thereby helping to keep the  temperature on interior parts such as armrests cooler by up to ten  degrees Celsius compared with conventional green glass.
Since the  innovative glass also shields against the sun's rays far more  effectively than conventional thermal insulation glass or sunblinds, the  occupants of the new Mercedes-Benz SL-Class will also enjoy the highest  level of climatic comfort at the same time. When driving with the roof  open would be unpleasant due to intense heat, the driver and passenger  are able to remain composed under the MAGIC SKY CONTROL roof - making an  important contribution towards driver-fitness safety, a concept which  Mercedes is well known for promoting. Even when the vehicle is at a  standstill the interior does not overheat, since the roof is switched to  darkened mode when powered off.
But MAGIC SKY CONTROL not only  benefits the occupants. Some of the strain is also taken off the air  conditioning, thereby saving on CO2 emissions.
The frame of the  three roof variants is now made of magnesium. This makes each roof  around six kilograms lighter than in the previous model, giving the car a  lower centre of gravity, and therefore better agility.
The  engineers have refined the operating mechanism for the roof and boot  lid. It now takes less than 20 seconds to open or close the roof  completely.
Sophisticated corrosion protection concept
The  aluminium bodyshell of the new SL offers no point of attack for  corrosion. A sophisticated surface protection concept ensures the  preservation of the brilliant look both of the outside skin and of the  underside of the sheet metal panels, thus simultaneously protecting the  renowned reliability and value stability of Mercedes-Benz vehicles. The  protection concept was developed and tested on the basis of the  environmental burden in different climate zones of the world and the  specific loads the vehicle is subjected to.
The foundation for  maximum corrosion resistance is formed by corrosion-resistant aluminium  alloys and design features, while the few steel vehicle components are  all fully galvanised. High-quality zinc/nickel coatings or special  electrochemical insulation measures prevent contact corrosion with  aluminium. All the seams are meticulously sealed, the surfaces protected  through cathodic dip priming and multiple coats of paint. Sectors  particularly exposed to corrosion are additionally protected with wax,  to ensure that the pristine aspect of the new car is preserved for a  long time.
Intelligent Light System and LED tail lights as  standard
The headlamps on the new SL have been enhanced.  As part of its standard specification, the new roadster is equipped  with the Intelligent Light System (ILS) featuring bi-xenon headlamps. A  driving direction indicator, sidelights and the daytime running lamps  with LED technology complete the Intelligent Light System.
The  tail lights on the new SL benefit from the advantages offered by the LED  technology. LEDs light up approximately 150 milliseconds faster than  conventional bulbs, plus they have a considerably longer life and  conserve current. In the SL's tail lights, the LEDs also light up with  differing intensity in a targeted manner in certain sections of the tail  lights, depending on the light function. This technology ensures an  unmistakable night design.
Rear reversing lights and rear fog  lamps are integrated into the rear bumper. The third brake light  featuring LED technology is integrated in the boot lid above the  Mercedes star.
Lightweight construction under the  microscope: Progress in detail
Right from the word go the  target was ambitious: the aim was for the new Mercedes-Benz SL-Class to  tip the scales weighing five percent less than the previous model.  Already declared the benchmark, the predecessor itself was a shining  example boasting various lightweight design measures, even including  bonnets made of aluminium. At the same time, the specifications book  prescribed more comfort, more output coupled with considerably reduced  consumption and fewer emissions, plus a more rigid bodyshell and even  more safety. These demands would render the vehicle heavier and not  lighter - that was clear. The experts calculated a weight increase of at  least 75 kilograms.
Only a lightweight construction on a totally  new level - which included all the vehicle components in the equation -  could reconcile these contradictory requirements. In actual fact, the  developers at Mercedes-Benz have succeeded in undercutting the ambitious  weight targets. The new SL500 weighs no less than 125 kilograms less  than the predecessor of the same name. This corresponds to a reduction  of 6.5 percent. Meanwhile the SL350 even manages to exceed the high  expectations even further - with its weight saving of 140 kilograms -  equating to 7.7-percent less.
Bodyshell. Converting the entire  bodyshell to aluminium cuts its weight by 24 percent in contrast with a  steel bodyshell featuring comparable properties (a weight saving of 110  kg). Even the upper door hinges consist of aluminium.
Damping. The  switch from absorber foams to sprayable acoustic compositions with  variable layer thicknesses which can be shaped according to  requirements, plus modified underbody panelling, results in weight  savings in the order of 2.5 kg.
The guide rails for the window  lift mechanisms are now comprised of aluminium instead of steel,  amounting to a weight saving of 0.5 kg.
Vario-roof in  magnesium/plastic design.The front part of the roof and the C-pillar are  produced in magnesium/plastic, plus there are additional optimisation  measures regarding the design of the tubular frame, rear shelf, rear  window frame and roof frame. The weight reduction amounts to 15 kg.
Glazing.  The windscreen is 0.5 millimetres thinner, with an acoustic film. The  weight reduction amounts to over 1 kg.
The rear windscreen is 0.7  millimetres thinner, resulting in approximately 1 kg less weight.
Interior.  The dashboard mount consists of a continuous IHP aluminium tube with  magnesium struts and moulded-on polymer brackets. The weight reduction  is 2.2 kg.
With the introduction of shift-by-wire technology, the  large shift lever has been replaced by a joystick-like lever. This  DIRECT SELECT gearshift system weighs only one sixth as much as the  automatic selector lever used in the preceding model. The weight saving  is 1.4 kg.
The boot floor is in the form of a polyurethane  honeycomb plate instead of the wood plate previously used. The  passenger's foot plate has been switched over to plastic from steel,  saving 1.5 kg in weight.
Seat. New seat structure with new  adjustment motors, but a standard-fit 4-way lumbar support and  crash-responsive head restraint. Weight savings: 11 kg.
Electrics.  Thanks to an intelligent dynamic load management system, two batteries  are no longer necessary; one 95 Ah battery in the boot is sufficient,  supported by a 12 Ah battery for the ECO start/stop function. Weight  savings: approx. 4 kg.
Every vehicle is given a customer-specific  wiring harness for the interior, cockpit and engine compartment. Thanks  to this tailor-made cable harness, additional weight in the form of  wires which are surplus to requirements can be saved - to the tune of up  to 0.4 kg.
The innovative Frontbass system avoids the need for a  separate woofer and door loudspeaker. Weight reduction: over 4 kg.
Axles.  The four-link front axle had already undergone extensive weight  optimisation for the preceding model, featuring steering knuckles and  spring links made of aluminium. The two front-axle halves now consist  entirely of this material. The integral support frame for the front-axle  halves, steering gear and engine is also produced in aluminium. Total  weight savings: 11 kg.
The rear-axle subframe consists of  high-strength steel with adapted panel thicknesses. It has been  optimised in accordance with the specific engine line-up for the SL350,  resulting in a weight reduction of 2.6 kg over the SL500.
Suspension,  Damping. The standard-specification semi-active adjustable damping in  the SL350 is lighter than the standard suspension system, saving 10 kg  in weight.
Brakes and pedals. Optimised brake cooling eliminates  the need for large and thus heavy brake discs on the front axle. Weight  savings: 3.8 kg.
Lightweight wheels. New standard-fit lightweight  wheels for the SL500 are around 15 percent lighter than cast wheels.  Weight saving: approx. 4 kg
Wheel bolts with a weight-optimised  head. Weight saving: approx. ¼ kg.
MAGIC VISION CONTROL  adaptive windscreen washing system: Visibility as if by magic
An  astonishing experience: the wiper blade glides over the badly soiled  windscreen of the new SL, without a sign of a cleaning water jet, the  occupants do not notice anything yet the windscreen is still cleaned!  The new SL is the first vehicle to be equipped with the adaptive MAGIC  VISION CONTROL wiper/washer system developed by Mercedes-Benz. It cleans  the windscreen without the splash of water that usually briefly  disrupts the driver's field of view in the case of conventional  windscreen washing systems - something that is especially unpleasant at  night or when the sun is low in the sky and at high speeds.
In  fact, the windscreen cleaning operation in the Mercedes-Benz SL-Class is  still performed with washer fluid in the conventional manner. The  innovation lies in the way the fluid is conducted to the windscreen in  order to clean it. This is done by means of water guides integrated on  both sides along the wiper blade - one on the left and one on the right -  with minute laser-cut spraying holes. Via these channels, the  innovative washer/wiper system always supplies washing fluid to the  windscreen discreetly, precisely where it is needed: just in front of  the wiper blade lip, according to the direction of movement of the  wiper. The holes are distributed along the entire length of the wiper  blade, being more closely spaced towards the outside of the blade, where  it sweeps a greater area, than closer in, where the area swept is  smaller.
Programs for summer, winter and cabriolet  operation
Mercedes-Benz controls the MAGIC VISION CONTROL  system intelligently via three partly autonomous wash programs - for  summer, for winter and for cabriolet driving. It is the first windscreen  wipe/wash system anywhere in the world to operate in this way. In  summer, small quantities of water are sufficient to remove a light  powdering of dust. In winter the dirt mixed with de-icing salt requires a  greater amount of water. The MAGIC VISION CONTROL system works in  accordance with the outside temperature, and it also automatically  adapts the washer fluid quantity to the surrounding conditions.
A  particularly interesting feature of the SL Roadster is the Cabriolet  function: when the hardtop is down, the electronic control system  reduces the amount of water, apart from which it demands the required  water mainly on the downward stroke of the wiper arm. This way the  windscreen can be conveniently cleaned during the journey and with an  open roof, without any of the water spraying into the vehicle interior.  Another pleasant side effect is that, since the washer fluid is directed  specifically and in a well-metered manner to the area to be cleaned,  one doesn't douse anyone else in the surroundings with water, either,  and it also doesn't distribute any spray onto the vehicles behind. At  the end of the day, a better cleaning effect is attained with up to half  the amount of washer fluid. It has therefore been possible to reduce  the volume of the washer fluid reservoir by 1.7 litres compared with the  preceding model. This in turn contributes to a reduction in weight and  consequently to greater efficiency.
Winter-proof thanks to  the heated system
On request the MAGIC VISION CONTROL  wiper blades are completely heated on the new SL, making Mercedes-Benz  the first manufacturer in the world to offer a fully heated wiper/washer  system. It consists of a washer fluid container heated through coolant  waste heat, electric heating for the entire hose system and, as a  newly-developed highlight, a fully heated wiper blade. This effectively  prevents the formation of snow on the wiper blades, so typical in  winter. To do this each of the spring rails of the blade is equipped  with a heater foil with an output of 35 watts per blade. It heats the  spoiler and the wipe lip. Snow and ice cannot freeze onto the blade; it  remains supple in winter, too, and always cleans well.
The heating  is also controlled as required according to the duration of operation  and the outside temperature. It is only below a temperature of minus 20  degrees Celsius that the system makes use of the entire system's maximum  output, 270 watts. Between 5 degrees above and 20 degrees below zero  the heating operates in an energy-saving mode and only requires the  output needed to thaw out the wiper/washer system and keep it free of  snow and ice.
Aerodynamics: Breezy, but never bothersome
Open-top  motoring should be nothing but sheer pleasure: smelling the forests and  meadows, hearing the birds singing, savouring the sound of the sea,  feeling the warmth of the sun. And in spite of this proximity to the  natural world, the occupants in the new SL do not have to relinquish  comfort. Even at higher speeds they are largely unaffected by any strong  winds. In this respect, just like its predecessor, the new luxury  roadster is unsurpassed by no other open-top two-seater.
First and  foremost it is the rigid aluminium bodyshell and - one of the brand's  hallmarks - sophisticated aerodynamics which ensure excellent comfort  during open-top motoring. The designers' intelligent and highly  efficient work has resulted in superb aerodynamic properties for the SL  in several respects. This means that the roadster earns top marks in no  less than four important disciplines within its segment:
- Best cd figure
- Wind noise on a par with a saloon
- Open-top motoring in maximum comfort
- Best anti-soiling measures
Top-class:  cd figure
The new SL shines with a cd figure of 0.27 (in  the SL350). Never before has a vehicle in the roadster segment achieved  such a low cd. At the same time, the cLR value (the coefficient of lift  at the rear axle), which is decisive when it comes to braking  stability, is reduced by 0.01. This ensures a lower lift at the rear  axle than at the front axle - which is important for comfortable, safe  handling at high speeds and/or when there is a crosswind.
The fact  that not only could the cd figure be cut to a record low but that it  was also possible to reduce the wind resistance as a whole is even more  astounding when taking into account the fact that the new SL's frontal  area is around four percent larger than that of its predecessor - due in  part to its wider track. The product of the frontal area and the cd  figure is, however, smaller.
Alongside a great deal of precision  work, some of the other factors which contribute towards the low cd  figure are:
- a complete engine compartment and underbody panelling concept,
- a spoiler lip on the top face of the boot lid,
- a specifically designed spoiler lip on the tail light,
- wheel spoilers in front of the front and rear wheels, and
- redesigned exterior mirrors positioned on the beltline and with a mirror base specially optimised for the new SL.
A newly developed aero  wheel which is part of the standard specification for the SL350 also  significantly reduces the wind resistance. Its rim section is largely  closed, which means that the air flowing through the wheel to the  exterior disturbs the air flowing past at the outside of the wheel than  is the case with a conventional wheel. Together with tyres which have  been specially tuned to this end, the aero wheel cuts the frontal area -  which is also a decisive factor in determining the wind resistance - by  0.01 square metres. This pays off in the form of a reduction in  consumption, which results in one gram per kilometre fewer carbon  dioxide emissions.
In order to minimise wind resistance even  further, the six-cylinder version of the new SL also employs an  adjustable radiator shutter. This consists of a large number of louvres  and is positioned between the radiator and the radiator fan. An actuator  fixed to the engine's cooling module can be turned to close or open the  flow path of the cooling air. In this way the flow of air through the  radiator and through the engine compartment can be regulated as  necessary. This means that if the engine has low-level cooling  requirements, the wind resistance falls, as do the fuel consumption and  emissions.
Top-class: wind noise on a par with that in a  saloon
Where wind noise is concerned, the predecessor of  the new SL was already the benchmark in its segment. But its successor  surpasses this high level. It is even possible to hold a conversation,  listen to the radio and make a telephone call at high speeds. This is  thanks in part to the new stand for the exterior mirror. Its shape  facilitates optimum flow; both when the inflow is straight and in the  case of crosswinds it causes only low wind noise.
The windscreen  fitted with multi-layer foil also contributes towards the exemplarily  low interior noise, combining a low component weight with good acoustic  properties. Low-frequency sounds which can arise through vibrations in  the vehicle's bodyshell can to a large extent be prevented by the new  SL's aluminium bodyshell, through design measures which were taken into  account and tested at an early stage.
Top-class:  maintaining a draught-free interior
Even at speeds of  around 200 km/h the new SL offers extraordinarily high comfort during  open-top motoring, setting new standards here. When the vario-roof is  closed and the side windows are lowered, a welcome breeze can be felt  during hot weather. Even putting the side windows up tangibly reduces  it. The occupants in the new SL enjoy a comfortable and virtually  draught-free ride as soon as they use a draught-stop. A conventional,  manually operated folding-frame draught-stop comes as part of the  standard specification. Covered with a finely meshed, synthetic textile  fabric, this draught-stop is mounted behind the seats and folded up by  hand. It covers the entire area behind the seat backrests as far as the  upper edge of the head restraints. It can be taken off and stowed in the  boot as necessary.
A highlight comes in the form of a new  electrically operated draught-stop which is available as an optional  extra. This new development can also be extended and retracted by the  driver or passenger during the journey, via a switch in the centre  console. If the switch is operated, a trapezoidal frame is unfolded  electrically, and when it reaches its final position a finely meshed  textile fabric covers it, thus keeping the area behind the occupants  virtually free of draughts. Once it has been retracted, the frame  disappears completely in the rear compartment trim cover.
The  innovative neck-level heating system AIRSCARF is also available as an  optional extra. It emits preheated air from an orifice in the head  restraint, and this warm air then wraps itself around the neck area of  the occupants like an invisible scarf, therefore even making it possible  to have the roof open when the temperature is cool, without any serious  inconvenience.
Top-class: anti-soiling measures
Clean  exterior mirrors and side windows are important factors where safety is  concerned, yet all too often drivers cannot take them for granted. In  this respect, the new SL profits from the detailed work carried out by  the aerodynamics engineers and can to a large extent ensure clear vision  for drivers - even when it is raining. This is achieved mainly through a  precisely tuned package of anti-soiling measures. The A-pillar trim  with a new shape features an aerodynamically and aeroacoustically tuned  front edge and a water guide channel on the top edge prevent water from  flowing from the windscreen to the side windows. The new exterior mirror  has also been optimised for journeys during rainy weather. Water guide  runnels and additional drip edges have been integrated into its housing,  and to a large extent they keep water away from the mirror glass, and  shift the break-away point of the droplets to the outside. As a  consequence of the aerodynamic measures the side windows soil only  slightly.
Engine and drive system: The power and the  economy
Rich power reserves plus modest fuel consumption -  this formula describes the fundamental characteristics of the new SL  models. They owe this in part to the two V6 and V8 units from the new  generation of BlueDIRECT engines from Mercedes-Benz. As is already the  case with the S-Class and the CLS, they now also enable the SL to  achieve previously unattained marks for efficiency in its segment. The  V8 in the new SL500 has at its disposal 4663 cubic centimetres of  displacement from which it achieves 320 kW (435 hp) - so in spite of  having around 0.8 litres less displacement that's some 12 percent more  than its predecessor (285 kW/388 hp). The consumption, meanwhile, falls  by up to 22 percent, with the torque increasing at the same time from  530 Nm to 700 Nm - an increase of 32 percent. The V6 engine for the  SL350 has the same displacement as its predecessor - 3499 cubic  centimetres - from which it now achieves 225 kW (306 hp). Whilst this  means that its output is 7 kW less than the engine in its predecessor  (232 kW/315 hp), as the torque simultaneously climbs from 360 Nm to the  current figure of 370 Nm, there is no perceptible loss of power - on the  contrary, in fact: when accelerating, the new SL350 even proves  superior. Plus the new V6 impresses with its outstanding consumption  figures. It is content with 6.8 litres over 100 kilometres, making it  almost 30 percent more economical than its predecessor (9.7 l/100 km).
Thanks  to the economy of both engines, it has been possible to decrease the  volume of the fuel tank from 80 litres to 65 litres. Nevertheless a  greater range is available than was the case with the predecessor.
Of  a torquey disposition when sprinting
The acceleration  times from 0 to 100 km/h go to prove that economy does nothing to dampen  torquey spirits. Despite a nominal reduction of 7 kW, the SL350 covers  this sprint in 5.9 seconds, which is three tenths faster than its  predecessor. From a standstill the SL500 races to the 100 km/h mark in  4.6 seconds, making it eight tenths faster than the previous SL500.
Both  engines are exemplary when it comes to in-gear acceleration, too. Proof  positive can be found in acceleration from 80 to 120 km/h in 4th gear,  for only good figures facilitate fast and safe overtaking on rural  roads. 5.5 seconds for the SL350 and 3.2 seconds for the SL500 make the  new SL's excellent characteristics in this discipline plain for all to  behold.
"The new BlueDIRECT engines in the SL with six and eight  cylinders form a unique synthesis of effortlessly superior power  delivery, comfort and consuption", comments Professor Dr Thomas Weber,  responsible for corporate research and development at Mercedes-Benz Cars  on the Board of Management of Daimler AG. "Both impress in the new SL,  delivering refinement of the highest calibre and exemplary environmental  acceptability."
The V8 is in a new league of its own
The  new V8 was systematically enhanced on the basis of the very successful  predecessor. Mercedes-Benz engineers primarily achieved a high output  for a lower displacement by using one turbocharger for each bank of  cylinders. The turbochargers were configured to provide high torque even  at low engine speeds - compared to the previous engine, the result is  an increase of more than 40 percent at 2000 rpm. A superb 700 Nm are  available between 1600 and 4750 rpm.
The V6 impresses with  its low fuel consumption and high comfort
The new  six-cylinder is a naturally aspirated engine. The most striking change  between the new V6 unit and its predecessor is a reduction in the  V-angle between the cylinder banks from 90 degrees to 60 degrees. This  enabled the balancer shaft counteracting primary vibrations to be  omitted, and as a result the driver registers an outstanding level of  comfort.
Innovative technology makes V6 and V8 engines fit  for the future
Both the new V6 and the new V8 from  Mercedes-Benz are derived from their predecessors. They have aluminium  crankcases, pistons and cylinder heads. The crankshaft, connecting rods  and valves are of special forged steel. Practically all the details  were, however, newly developed or revised with the aim of achieving more  fuel economy, more output and more refinement.
The technology  package in the new engine generation includes a number of new  developments that are unique in this combination:
- In combination with multi-spark ignition, a further developed, 3rd-generation direct fuel injection system with spray-guided combustion and piezo-electric injectors offers further possibilities for fuel savings - in the V8 by means of an improved, homogeneous combustion process, and in the V6 by a new, stratified combustion process with a considerably extended characteristic map and fuel-efficient lean-burn technology.
- In conjunction with the ECO start/stop function, shift point adjustment and systematic friction-reducing measures, improvements in day-to-day fuel consumption of up to 30 percent are possible.
- Power consumption by ancillary units has been reduced. These include an optimised water pump with 2nd-generation thermal management, a demand-controlled oil pump, a volume-controlled high-pressure fuel pump and an intelligent generator management system.
ECO  start/stop function with direct-start
The  standard-specification ECO start/stop function operates with  starter-supported direct-start. This means that when the engine is  switched off, the attitude of the crankshaft is registered by a new  crankshaft sensor so that the engine control unit knows the positions of  the individual pistons. On restarting, it can then select the cylinder  that is in the most suitable position for first ignition. After the  starter has briefly turned over the engine, reliable injection, ignition  and combustion is immediately possible there.
An additional,  demand-controlled electric transmission oil pump supplies the clutches  of the automatic transmission with oil pressure prior to starting, so as  to enable a swift resumption of the journey after direct starting of  the combustion engine via the ECO start/stop function. The starter motor  (starter) has also undergone thorough modification: it is now designed  to be highly durable, ensuring that it will last a car's lifetime in  continuous urban driving involving frequent auto-starting. In addition,  the on-board electrical system is supported by a second battery. As is  the case with the starter battery (95 Ah), the "auxiliary battery" (12  Ah) also features maintenance-free AGM technology (AGM = absorbed glass  mat).
Intelligent alternator management
Its  intelligent alternator management also contributes to the luxury  roadster's sensitive treatment of energy. When the battery is charged to  more than 80 percent, the alternator is governed to take load off the  engine. The energy required in this operating state is supplied by the  battery. If the driver removes their foot from the accelerator pedal or  applies the brakes, kinetic energy is recovered and fed to the battery.
Automatic  transmission for less consumption and more fun at the wheel 
All  Mercedes-Benz SL-Class models come with the 7G-TRONIC PLUS automatic  transmission as standard. Now in its sixth generation, the multi-ratio  automatic transmission was developed by Mercedes-Benz and has been  produced since 1960. The new version has once again been thoroughly  revised to optimise consumption and comfort compared with its  predecessor. The new generation of the torque converter provides an  improved dynamic response and reduced noise and vibration levels thanks  to a new hydraulic circuit, as well as enhanced dampers and an optimised  torque converter housing. The extreme wheel-slip reduction of the  torque converter housing, combined with
- larger mechanical damper de-coupling, helps to reduce consumption significantly;
- in addition, the gearshift program in ECO mode has been changed in favour of lower engine rpm at cruising speeds;
- friction-optimised bearings and seals plus a new automatic transmission oil (FE-ATF) with reduced viscosity in conjunction with an optimised additive package.
This  results in more driving enjoyment than was the case with the  predecessor transmission - and also improved smoothness, not to mention  an average of seven percent less consumption (in the NEDC).
What's  more, the increased durability of the new oil also brings with it new  oil-change intervals from 50,000 (old) to 125,000 kilometres (new).
DIRECT  SELECT gearshift with designer chic and athletic allure
Mercedes-Benz  is equipping the new SL with the newly developed DIRECT SELECT  gearshift in the centre console - the first vehicle with an automatic  transmission to receive this honour. In so doing, the premium brand is  establishing a completely new generation of central gearshift for  vehicles featuring shift-by-wire (ShW) transmission technology. Its  small control lever, reminiscent of a high-calibre joystick, has a  driver-oriented position, being installed on the centre console. Its  striking design not only underlines the sporty character of the  roadster; it also emphasises the high quality of the SL with its  exquisite touch and feel, superb ergonomics and unique look.
In  addition to an Eco program, the 7G-TRONIC PLUS in the new SL also offers  a sports-oriented automatic program. Over and above this, the driver  can also select a manual shift program which they operate via the  paddles on the steering wheel - which also come as part of the standard  specification.
The two automatic programs automatically adjust on a  continuous basis in line with the driver's behaviour. By way of  example, if they step on the accelerator pedal more dynamically than  before, the shift points automatically move towards more sportiness. In  the ECO mode, the shift program is configured differently for lower  engine speeds during cruising, thus saving fuel.
In the sportily  oriented automatic program, the output is available more spontaneously  and it shifts faster. The double-declutching function and active  downshifts have been systematically enhanced. During heavy braking, the  transmission shifts down considerably earlier, so higher engine speeds  make the acceleration which follows easier. The double-declutching  function, in which the engine speed is actively raised with an abrupt  acceleration, ensures faster and more comfortable downshifting. The  concomitant acoustic response underlines a sporty driving style and  enhances the unique roadster feel.
In the manual transmission mode  controlled using shift paddles on the steering wheel, the engine  responds to the throttle over a steeper characteristic pedal curve.  Selecting the gear via the steering-wheel gearshift buttons facilitates  minimal shift times and emphasises the sporty double declutching. In  manual mode, the gear indicator in the instrument cluster moves to a  separate section of the colour display, where it shows the seven  available gears plus the gear currently selected.
Chassis  and suspension: Best contact with the road
Powerful when  accelerating, effortlessly superior at every speed, zappy on winding  stretches - the new SL is a shining example, displaying perfect manners  on all the world's roads and in all driving situations. What's more, it  also pampers all the senses with any amount of fun at the wheel. For  these emotive experiences SL drivers can thank the potent engines - and  above all the sporty, agile tuning of the suspension - which is  nevertheless very comfortable, being offered in the form of two  different systems for the SL:
The Mercedes-Benz SL-Class features  semi-active adjustable damping as standard. The optional active  suspension system ABC (Active Body Control) is offered as an  alternative.
The spring struts which come as part of the standard  equipment combine a steel spring with a continuously adjustable damper.  Its damping properties can be varied via an electrically controlled  valve.
Continuous adjustment of the damping in accordance with the  respective driving situation is taken care of fully automatically by  control electronics which record the driving condition in question via  sensors. The control unit uses the sensor data to determine the  necessary damping forces for optimum comfort and handling. On this basis  it steplessly regulates the damping valves at every wheel within a  broad damping characteristic so that sprung mass vibrations such as  lifting, rolling and pitching are minimised on uneven roads. As a  result, the new SL gives its occupants a smooth ride even on poor roads,  without relinquishing any driving dynamics.
The semi-active  adjustable damping also rapidly counteracts sprung mass vibrations  caused by the driver, by adjusting the damping characteristics. By way  of example, the dynamic anti-roll and anti-pitch support compensates for  pitch ensuing from braking and accelerating, and quickly and  effectively stems rolling motion which is initiated above all by  cornering or jerking the steering wheel during a dynamic evasive  manoeuvre. Torsion bars at the front and rear axle help to reduce wide  roll angles when cornering, and positively influence the  understeer/oversteer characteristics.
Setting the basic  characteristics of the suspension is still left to the driver, however,  using a switch that enables them to choose from a broad spectrum ranging  from comfortable to sporty damping characteristics. At the touch of a  button they can therefore have a chassis and suspension set-up available  which places more emphasis on comfort, for instance, whilst if they  choose the sports setting, they are opting for a driving experience with  a very high level of dynamic response.
Sports suspension  in the AMG Sports package
A variant of this suspension is  offered in the AMG Sports package. This sports suspension lowers the  roadster by ten millimetres, the spring strut and torsion bars are  configured to be ten percent more rigid and the parameterisation of the  adjustable damping is selected in such a way that the sprung mass  vibration is dampened more strongly - all measures which underline the  vehicle's sporty character.
ABC suspension for high levels  of comfort
As an option the new Mercedes SL is available  with the unique active suspension system ABC (Active Body Control) as  an alternative. It has been further improved for the new SL by the  Mercedes-Benz chassis and suspension specialists. This system's highly  effective control elements are spring struts with a hydraulic steel  cylinder arranged in line with the steel spring. When this cylinder  retracts and extends, it actively adjusts the length of the spring and  therefore the spring force in the spring strut. This eliminates the need  for torsion bars at the front and rear axle.
With this technology  an automatically controlled electronic system permanently adjusts the  suspension to suit the driving situation and the road condition without  any perceptible delay. This means that the active suspension system ABC  can raise comfort to a high level, whilst simultaneously improving the  roadster's driving dynamics. This is possible as it almost completely  compensates the vehicle body's rolling and pitching movements when  accelerating, braking and cornering. In addition to this, at the touch  of a button it offers a unique, further increased spread of suspension  settings between sports and comfort.
As the vibrations initiated  by irregularities in the road surface are greatly reduced, the occupants  in the SL experience a vehicle with perfect absorption capacity on poor  roads. Above all it is alternating sprung mass vibrations  ("cross-pitching") which are extremely minimal.
Sprung mass  vibrations which arise through the driver's influence are also almost  entirely ironed out - this is the case, for instance, when the body  rolls during steering or when there is pitching during braking and  accelerating. The occupants experience a vehicle which drives "as if on  rails", but without having to pay for this with the usual reduction in  ride comfort which is typical of sports suspensions.
As the ABC  system modifies the roll torque distribution depending on the driving  speed, the driver experiences handling which changes with the driving  speed. It varies from motoring pleasure where one can afford it in  driving dynamics terms to directional stability where it is most needed.  In other words, on winding rural roads the roadster moves with nimble  agility, and on motorway stretches it stays safely on track and does not  worry the driver with any nervous reactions.
The ABC system is  also fitted with a hydraulic all-round level control system, thus  ensuring a constant vehicle level irrespective of the load. When the  engine is running, the driver can raise the level of the vehicle at the  touch of a button, both when the vehicle is at a standstill and during  the journey. Thanks to a new feature in the SL, if the level is raised  by 50 millimetres in this way, the ground clearance for rough roads or  ramps is increased. In addition, the SL fitted with ABC is automatically  lowered by up to 13 millimetres at high speeds, thus lowering the  centre of gravity and wind resistance - and therefore also the fuel  consumption.
More track, less unsprung weight
The  track and wheel suspension are the same in the case of both suspension  variants. In favour of sporty, agile and handling which can be safely  kept under control, the new Mercedes-Benz SL-Class has a considerably  wider track than the predecessor (front axle plus 38 mm, rear axle plus  63 mm).
At the front axle, the tried-and-trusted principle of the  4-link front suspension has been adopted from the previous model series.  It achieved superb results where comfort, dynamism, agility plus active  and passive safety are concerned. Most importantly they are  characterised by two individual links (a torque strut and a spring  link), which are included in place of a lower wishbone. In conjunction  with the ABC suspension no torsion bar is necessary.
In order to  optimise the front axle even further in terms of weight, in the new SL  the steering knuckle and the spring link are also made of aluminium. The  lower front axle elements, the steering gear and the engine mounts are  linked with an aluminium assembly carrier which is directly bolted to  the body.
A lightweight construction was also systematically  implemented at the rear axle, too. In order to reduce the unsprung  masses, virtually all the suspension parts are made of aluminium, as is  the subframe with load-matched panel thicknesses. The weight-reduced  rear axle carrier consists of high-strength steel.
But the focus  was not just on saving weight when developing the rear axle; the  engineers have also optimised the kinematics and elastokinematics, with  the objective of achieving more agility. Other results of the new  configuration are lower forces, which considerably increases comfort. An  additional support linking the rear subframe bearing to the bodywork  also has a positive effect on the new SL's ride comfort. It increases  the introduction rigidity - a parameter whose properties include  excellent road roar characteristics where NVH (noise, vibration,  harshness) qualities are concerned. Thanks to these constructive  measures relating to materials technology, the new luxury roadster  offers a chassis with outstanding comfort coupled with excellent driving  dynamics.
Like its predecessor, the new SL with adjustable  damping also has an anti-roll bar, which is mounted directly at the rear  axle and assembled together with the subframe, and serves to reduce the  connection points with the bodyshell.
The chassis has a virtually  neutral configuration, pleasing sporty drivers. In particular in the  range from 60 to 130 km/h it reacts with enormous agility, and therefore  facilitates a great deal of fun at the wheel on rural roads. In so  doing the SL allows lateral accelerations which are impressive even for a  sports car. Two different programs can be selected for the ESP®. The  control interventions from the more sportily tuned variant allow  side-slip angles during accelerated cornering - offering adept drivers  plenty of motoring pleasure. At the same time it can be driven more  easily and safely at higher speeds.
Electric Direct-Steer  system for more driving dynamics
The broad spread of  suspension settings is supported by a new electromechanical Direct-Steer  system with speed-sensitive steering power assistance and a variable  steering ratio that changes according to the steering angle. The ratio  is very indirect when the steering is centred, which ensures good  straight-line stability and therefore a high level of safety. In  contrast to other variable steering systems, the ratio of the  Direct-Steer system decreases rapidly after a steering angle of 5  degrees, becoming extremely direct from a steering angle of just 100  degrees. Only relatively small steering movements are then needed to  make course corrections.
In contrast to the predecessor, the  Direct-Steer system optimises the ratio course. This enables the new SL  to shine with yet more agility, making cornering even more fun as a  result. At the same time, through the new ratio course the maximum  steering effort required when parking or turning is reduced by about 15  percent. This means that only 2.2 turns of the steering wheel from limit  to limit are now necessary.
This has the following effect in  practice: even at urban driving speeds, the driver needs to perform less  pronounced steering movements, making changes in direction possible  more rapidly and with less effort. The effect of the Direct-Steer system  is even more impressive on winding country roads, where only small  steering movements are sufficient to steer the vehicle. Even on tighter  bends, the driver's hands hardly need to change their grip on the  steering wheel. Rapid sequences of bends can be mastered safely and  precisely, and with enormous enjoyment.
Despite its remarkable  effect, the key component of the Direct-Steer system is a simple  steering rack. Its secret lies in the teeth cut into it. In the mid-area  these are slightly wave-shaped, with varying flank profiles. To both  sides the teeth are spaced at varying distances apart. The change in  steering ratio is therefore produced by purely mechanical means. With  this ingenious solution, Mercedes engineers have been able to dispense  with the elaborate actuators and complex sensor systems used by other  variable steering systems. The advantages of the Direct-Steer system  therefore include very low susceptibility to faults and low weight.  Moreover, the system always responds predictably and in the same way at  each steering angle, while other variable steering systems sometimes  require rapid adaptation by the driver in rapidly changing situations.
Instead  of hydraulically, as is the case with the familiar speed-sensitive  steering from Mercedes-Benz, the Direct-Steer system in the SL regulates  the steering force electrically. This is taken care of by an electric  motor - positioned axially parallel to the toothed rack - which  transfers its power to the ball screw as a rotary movement via a toothed  belt. The electric motor, drive unit, control unit and sensor system  are integrated in a compact unit.
The control unit evaluates a  large number of input variables in order to configure the steering  torque optimally in accordance with the situation in question. A torque  sensor determines the necessary assistance required at the steering-gear  input shaft. In so doing the electronics take into account, for  example, different vehicle axle loads. Due to the different engine  weights, the characteristic maps for six-cylinder and eight-cylinder  models are proof positive of the engineering artistry that lies behind  the system.
Further advantages of the electric steering:
- More active response: the electronics support the steering return, meaning that drivers hardly need to steer in order to return to the centre position.
- Lower consumption: as output is only called up when the driver is actually steering, the consumption falls by up to 0.3 l/100 km compared with the hydraulic Direct-Steer system.
- Active parking: with the electromechanical Direct-Steer system the Automatic Parking Control (APC) system can be offered in the Mercedes-Benz SL-Class for the first time.
Assistance for critical  road surface conditions
A further assistance function  has been realised in the new SL thanks to the electromechanical steering  power assistance - the Steer Assist system: it can support  stabilisation of the vehicle if the vehicle brakes on a road surface  with different friction (µ-split) on the left and right, making it pull  to one side. Drivers can find themselves confronted with this situation,  for example, on a road surface which is covered with ice on one side.  When braking, the vehicle then turns in the direction of the high  friction - referred to by experts as a yaw impulse.
In this case  the steering assistance system indicates to the driver via the steering  wheel that they should countersteer in the correct direction in order to  compensate for the yaw impulse caused by the difference in friction -  until the vehicle has stabilised again. In order to do this the control  unit evaluates the difference between the ABS pressures on the right and  left, giving an indication of different road surface friction  coefficients, and it also includes the ESP® data which register  oversteer in this sort of situation.
By way of indication, the  electric steering power assistance impresses a steering torque which  supports the driver's own reaction like a suggestion. This steering  torque, which causes the driver to steer correctly through a light  impulse, is hardly perceptible, and most of the time it is not even  noticed at all. Nevertheless the assistance function is effective.  However the steering assistance system merely provides an indication of  the direction in which the driver should steer in order to stabilise the  vehicle; it does not overrule the driver.
Brakes for  sporty driving enjoyment
The new SL has adopted the  proven braking system with a dual-circuit brake and the split of the two  braking circuits between the front and rear axle from the predecessor  model. At the front all the variants are equipped with newly developed  4-piston fixed-calibre brakes with an aluminium monobloc design and  perforated brake discs. 1-piston combined floating brake callipers are  fitted at the rear.
In order to be able to provide the required  output from the braking system, the heat arising at the brakes must be  removed as quickly as possible. This is why special attention was given  to aerodynamically favourable and highly effective brake cooling. On the  basis of different wind tunnel and road tests, the aerodynamics  engineers developed a system comprising several components for targeted  air ducting in the front axle area. A brake air channel has been  integrated into the front engine compartment trim in order to guide the  air over the front wheel spoiler in a targeted manner and steer it onto a  guide blade. The guide blade fixed to the front suspension link diverts  the air coming from the brake air channel over the brake discs to the  exterior. Together with a front matched wheel spoiler, this has achieved  effective cooling of the brakes. The newly developed brake cover plates  consist of steel at the front axle and aluminium at the rear axle.
Electric  parking brake with emergency braking function
As a new  feature in the SL, the electrically operated parking brake helps in the  design of a generous interior. Its switch is located in the dashboard,  under the rotary light switch. Pressing this engages the electric  parking brake, and pulling releases it. It is also released  automatically as soon as the engine is running, the transmission is in  the D or R position, the driver has a fastened seat belt and the  accelerator is operated.
Under normal circumstances, irrespective  of the duration of operating, the electric parking brake only closes the  responsible combined floating brake calliper at the rear axle fully and  for a sustained period when the vehicle is at a standstill or at speeds  below 4 km/h. Provision has also been made for an emergency braking  function: if the driver pressed the electric parking brake at a speed  higher than 4 km/h, the SL brakes to a safe stop with the aid of the  service brake. In this case, the emergency braking function is taken  care of by the hydraulic unit of the ESP®, with the brake lights also  lighting up.
The emergency braking is interrupted as soon as the  control element is no longer kept depressed.
Torque  Vectoring Brakes: ESP® helps with the steering
The new SL  includes the Torque Vectoring Brakes system as part of its standard  specification. This ensures an additional safety margin at the physical  limits, makes the roadster even more agile and therefore enhances its  sportiness. The system achieves this with targeted, one-sided braking  intervention by the Electronic Stability Program ESP® at the inside rear  wheel when cornering. If ESP® detects a tendency to understeer, the  Torque Vectoring Brakes generate a defined turning or yawing moment  around the vehicle's vertical axis within fractions of a second. Thanks  to the different torque distribution that results, the SL turns into the  bend under precise control without any loss of handling dynamics. The  advantage of this solution over complex mechanical components such as an  active steering rear axle, additional multi-disc clutches or an active  differential is that the Torque Vectoring Brakes can be implemented  without an increase in vehicle weight and therefore no disadvantages in  terms of fuel consumption.
Wheels and tyres - a broad base  for the SL
As part of its standard specification the  SL350 is fitted with 17-inch light-alloy wheels with 255/45 R17 tyres -  options ranging up to 19-inch wheels are available for selection on  request. The SL500 is shod as standard with 18-inch wheels with  mixed-size tyres (8.5 J x 18 ET 35.5 with 255/40 R 18 tyres at the  front, and 9.5 J x 18 ET 47.5 wheels with 285/35 R 18 tyres at the  rear).
Safety: Top technology for the greatest possible  safety
Mercedes-Benz drivers are safer than drivers of  other brands when out on the roads. This is the result of an  investigation carried out by Mercedes-Benz accident research on the  basis of official, anonymised random data checks by Germany's Federal  Statistical Office. It underlines the efficacy of the comprehensive  Mercedes-Benz safety philosophy. This involves the experts not  contenting themselves with achieving rating targets, but working  intensively on attaining a level of safety which far exceeds the  standards stipulated by the world's legislators. An important measure of  their work is not the laboratory or crash test facility, but actual  accident incidents. The results of the work carried out by the safety  experts at Mercedes-Benz is known as Real Life Safety, a concept which  is based on research into thousands of accidents. Using this irrefutable  evidence, for their holistic safety concept they have developed or  initiated most of the assistance systems which today effectively support  drivers and have been adopted by many of the company's competitors.
"The  new Mercedes-Benz SL sets new standards for roadsters and can  confidently be referred to as the safest roadster in the world", remarks  Professor Dr Rodolfo Schöneburg, Director of Passive Safety at  Mercedes-Benz. "The rigid aluminium bodyshell offers superb  preconditions for a stable occupant cell, as well as for precisely  defined deformation zones. This provides optimum protection for the  occupants in the event of an accident. But we do not just think about  those inside the vehicle - we also consider the other road users, for  instance through effective pedestrian protection measures or assistance  systems which also protect other motorists."
During the  development process for the new Mercedes-Benz SL-Class the requirements  of Euro NCAP and other rating institutes were taken into account. The  basis for this is a new light-alloy bodyshell which is formed mainly by  extruded sections and cast nodes made of aluminium. It facilitates a  light yet stable cell compound for a highly rigid occupant cell. In  conjunction with this the tail end and front are designed in such a way  that in the event of an accident they can absorb high forces through  deformation, thus considerably reducing the strain on the occupants in a  crash in accordance with the principle of the crumple zone. The crash  boxes behind the bumper trim and an exchangeable front module ensure  that the damage sustained during a front impact at up to 15 km/h can be  limited.
Protection in the event of an overturn
The  occupants in the new SL enjoy good protection in the case of a  potential overturn, too. A-pillars in a steel/aluminium material mix and  two roll-over bars can protect the passenger compartment. Normally the  two roll-over bars are completely recessed, so they do not interrupt the  look of the elegant, luxury roadster's flowing lines. They are located  in two cartridges fixed to the bodyshell in the area behind the seat  backrests. If the system of crash sensors detects a potential overturn,  the airbag control unit emits a signal and the deployment mechanism is  activated. Two preloaded pressure springs per cartridge see to it that  the roll-over protection shoots to the support position in fractions of a  second.
Headbag and crash-responsive head restraints
The  restraint systems with two-stage driver and front passenger airbags  have been enhanced. A headbag provides generous lateral protection for  the head impact area. An additional thorax airbag in the seat backrest  can protect the upper body in the event of a side impact. The seat  belts, with inertia-reel tensioners and belt force limiters, serve to  highlight the high safety standards of Mercedes-Benz.
Another new  feature finding its way into the standard equipment of the SL comes in  the form of the NECK-PRO crash-responsive head restraints, developed by  Mercedes-Benz. They can support the driver's and passenger's head in the  event of a rear impact and reduce the risk of whiplash. Also fitted as  standard is automatic child seat recognition. The ISOFIX system is  available as an optional extra.
Protection for pedestrians
The  new Mercedes-Benz SL-Class Roadster uses the latest technology in the  area of pedestrian protection, too. A sensor system is able to register  an impact with a pedestrian and can ensure that the bonnet is  immediately raised by 85 mm in the rear section. This creates additional  space between the bonnet and the components in the engine compartment.  This in turn results in comparatively lower acceleration values for the  head of a pedestrian during the impact, thus reducing the overall risk  of injury.
The deformation properties of the bonnet have also been  specifically designed to meet the requirements concerning pedestrian  protection. It consists of aluminium with a homogenous reinforcement on  the inside of the bonnet and can therefore further reduce the loads in  case of an accident. The SL's "soft nose" also provides a large impact  area, whilst the foam density and geometry in the front bumper have been  optimised for reduced loads during leg impact with the pedestrian.
Only  available from Mercedes-Benz - the anticipatory occupant protection  system PRE-SAFE®
An additional safety highlight is the  standard-specification anticipatory occupant protection system  PRE-SAFE®, a system developed by Mercedes-Benz and unique throughout the  world. If it detects an acute risk of an accident, it reflexively  activates precautionary protective measures for the vehicle occupants,  also including the reversible, electromotive belt tensioning function  which ensures that the occupants are better secured so that the seat  belts and airbags are able to perform their protective function to the  full during an impact. Mercedes-Benz developed PRE-SAFE® on the basis of  research into actual accidents, and is the only manufacturer in the  world to offer such a system.
Following an accident -  optimally prepared
Mercedes-Benz's holistic safety  concept involves considering the phase after an accident. This is why  the new SL has numerous post-crash measures incorporated on board which  facilitate rapid assistance should the worst come to the worst:  depending on the type of accident and the impact severity, the doors can  be automatically unlocked, the interior lighting activated and the side  windows opened by 50 millimetres to provide better ventilation in the  interior. In addition to this, the steering wheel can be slid upwards.  The concept is completed by the Guidelines for Rescue Services and the  rescue cards which can be downloaded from the internet free of charge  and which can serve as a valuable support for fire brigades.
ATTENTION  ASSIST and ADAPTIVE BRAKE as standard
The new SL also  features a unique combination of driver assistance systems which help to  avoid accidents. These include the drowsiness detection system  ATTENTION ASSIST, for example. Thanks to this system, the roadster  develops a precise feeling for the level of attentiveness of the driver  and can provide an early warning of overtiredness.
Also making up  part of the standard equipment specification is the ADAPTIVE BRAKE. It  comprises ABS, the acceleration skid control system ASR and also active  yaw control (GMR). In addition, it features the following functions:
- it supports the driver when moving off uphill, by preventing the vehicle from unintentionally rolling back;
- it also keeps the vehicle stationary without having to keep the brakes applied continuously - for example when waiting at traffic lights;
- as soon as the driver abruptly steps off the accelerator, it brings the brake pads into light contact with the brake discs as a precautionary measure, so that the necessary braking pressure can be attained quicker in the possible event of emergency braking;
- in wet conditions it applies light brake contact, without the driver even noticing, to dry the brake discs.
The  ADAPTIVE BRAKE works in conjunction with the equally adaptive brake  lights. In emergency braking situations, it warns vehicles behind with  rapidly flashing brake lights.
PRE-SAFE® Brake: autonomous  partial and emergency braking in response to a serious risk of a  rear-end collision
Available as optional extras are the  DISTRONIC PLUS proximity control as well as the PRE-SAFE® Brake, already  tried and tested in other Mercedes-Benz models. The two systems  together and can initiate emergency braking automatically on detecting  an acute risk of an accident.
In normal driving conditions, the  radar-based DISTRONIC PLUS proximity control adjusts the distance to the  vehicle in front automatically. If necessary, it can apply the brakes,  even bringing the SL Roadster to a stop, and accelerate it again. This  takes some of the strain off the driver, particularly in  bumper-to-bumper driving conditions. If the distance starts to narrow  too quickly, the system gives the driver visual and acoustic warnings,  thereby prompting the driver to take action, at which point they are  also supported by Brake Assist PLUS (BAS PLUS).
If the systems  detect the acute danger of a rear-end collision and the driver fails to  respond to visual and acoustic warnings, the electronics activate the  PRE-SAFE® Brake in preparation for autonomous braking. This happens in  two stages:
Around 1.6 seconds before the calculated impact point,  the car initiates autonomous partial braking with around 40 percent  (approx. four m/s²) of the maximum braking power, gives the driver an  additional, haptic warning of the impending impact and as a precaution  activates the reversible PRE-SAFE® occupant protection systems.
If  the driver still fails to react, the PRE-SAFE® Brake activates the  maximum braking power around 0.6 seconds before the now unavoidable  collision - this emergency braking can greatly reduce the severity of  the impact. The system therefore acts like an "electronic crumple zone",  offering the car occupants even greater protection.
The PRE-SAFE®  Brake is active at speeds of between 30 and 200 km/h when moving  vehicles are detected in front of the car. The system also reacts if the  car approaches a stationary queue of traffic, providing the car's speed  is below 70 km/h.
The functionality of DISTRONIC PLUS has been  enhanced even further. It now reacts earlier to vehicles which cut in,  and the car accelerates quicker when changing lanes itself and where the  overtaking lane is clear. Thanks to the incorporation of information  from digital maps (navigation mode), automatic control has also been  further refined.
Intelligent Light System - good vision at  all times
The Intelligent Light System also comes as  part of the standard specification. It offers variably controllable  headlamps with five different light functions which are adapted to suit  driving and weather situations commonly encountered. They switch  themselves on depending on the prevailing driving situation, offering  the motorist a considerably greater field of vision:
- The country mode distributes the light from the low-beam headlamps in such a way that the left edge of the carriageway is illuminated more brightly and across a larger area.
- The motorway mode switches on from a speed of 90 kilometres per hour and enlarges the field of vision by as much 60 percent.
- The cornering light function is automatically activated when the main headlamps are on and if the driver operates the indicator or turns the steering wheel at a speed below 40 km/h. The low-beam headlamps and fog lamps then illuminate the side area ahead of the vehicle to a range of around 30 metres at an angle of up to 65 degrees.
- The active light function improves illumination of the road on bends by up to 90 percent.
- The enhanced fog light function works by pivoting the left-hand bi-xenon headlamp outwards by several degrees and lowering its beam. This provides brighter illumination of the inner half of the road.
Adaptive  Highbeam Assist is also on board as part of the standard specification:  when vehicles are detected ahead of or approaching the vehicle, this  system automatically dips the beams and adjusts the range of the  headlamps according to the distance.
The assistance  systems spring into action
Those wanting to can choose to  extend the potpourri of assistance systems in the new SL even further.  They provide extra doses of both safety and comfort. As an option  Mercedes-Benz can equip the roadster with the following helpful  features:
- Speed Limit Assist: it is able to detect speed limit signs using a camera on the inside of the windscreen and indicate the respective detected speed limit on a display in the instrument cluster and in COMAND. (Standard-fit in conjunction with COMAND online).
- Active Blind Spot Assist: it warns the driver when changing lanes if a risk of collision is detected due to another vehicle in the neighbouring lane being in the blind spot of the exterior mirror. If the driver ignores the warning and nevertheless initiates the lane-changing manoeuvre, the Active Blind Spot Assist intervenes. A brake actuation counteracts the collision course. (Part of the driver assistance package with DISTRONIC PLUS including the PRE-SAFE® Brake and Active Lane Keeping Assist).
- Active Lane Keeping Assist: this system kicks into action if the Mercedes-Benz vehicle inadvertently drifts over a solid line to the right or left of a lane. In such a case, a warning sign in the instrument cluster and vibrations in the steering wheel warn the driver. If the driver does not heed the warning in the case of a solid line, Active Lane Keeping Assist can use the ESP® to brake the opposite wheels and thereby prevent the vehicle from crossing the solid line. (Also part of the driver assistance package - please see above).
Hands off  the steering wheel when parking
Active Parking Assist  will answer the prayers of many drivers in the chronically congested  traffic areas of Europe: the SL can not only detect parking spaces, but  also help with the parking itself. This is made possible thanks to a  combination of the new electromechanical Direct-Steer system (please see  the chapter on the chassis and suspension) and a series of ultrasonic  sensors. This convenience system features the following functions:
- Measurement of potential parking spaces lengthwise to the direction of travel - even in slightly curved bends - up to a drive-by speed of 30 km/h. The parking spaces must be at least one metre longer than the vehicle.
- Calculation of a suitable parking manoeuvre in order to park the vehicle parallel to the kerb.
- Automatic steering in order to perform this parking manoeuvre.
- Automatic steering in order to exit the parking space. This is only possible if the parking space was entered using Active Parking Assist.
Two ultrasonic sensors take care of  the search for suitable parking spaces lengthwise in the direction of  travel. They are integrated in the front bumper, on the left and right.  If the speed falls below 30 km/h, a "P" symbol in the instrument cluster  signals to the driver that the active search for a parking place has  been started automatically. If the system has found a potential parking  space, an arrow indicates this alongside the "P" symbol. As standard,  the arrow shows parking spaces on the passenger side. If the indicator  on the driver's side has been activated, it shows potential parking  spaces on the driver's side.
It is up to the driver to assess  whether the free area designated by the system is indeed actually a  parking space. Even during the parking procedure the responsibility  remains with the driver. They activate the accelerator and brake pedals  during parking. The Active Parking Assist takes care of the steering and  for orientation it uses the two front ultrasonic sensors as well as  four further sensors in the rear bumper. During parking, the roadster  must not move faster than 10 km/h. The automatic parking manoeuvre is  configured for a maximum of five turns  (backwards-forwards-backwards-forwards-backwards). Once the vehicle is  standing correctly in the automatically selected parking space, the  system aligns the wheels.
The Active Parking Assist switches  itself off as soon as the driver intervenes in the automatic turning of  the steering wheel, if the system is turned off via the PTS button  (Parktronic sensor), both if the driver's seat belt buckle or the  driver's door is open, or if there is a system error. Nevertheless the  familiar PARKTRONIC function remains available without any restrictions.
Infotainment:  The fully integral sound of tomorrow
As a rule, those  gifted with a sensitive sense of hearing cannot expect much listening  enjoyment in a roadster. Even good car radios and CD players are  disappointing under these arduous acoustic conditions. Instead, in  open-top cars, the music flies away with the wind; it frays and breaks  up in all directions without its acoustic base - passengers generally  have to be satisfied with a woolly "sound carpet", or close the roof.  Open-air pleasure and musical enjoyment could hardly be expected in a  roadster. A great part of the blame for this lies with the location of  the bass loudspeakers in the doors or under a seat. Mercedes-Benz now  presents a solution to this conflict: the unique Frontbass system, which  at last creates the conditions for a concert hall ambience in a  roadster too. In the new SL, the Frontbass system is celebrating its  world premiere.
Crisp bass sound from the footwell
The  principle sounds simple: Instead of being placed in the doors in the  usual way, in the new SL generation the bass loudspeakers are installed  in the footwell in front of the driver and passenger. This is not  possible with traditional vehicle shell structures, but the two front  longitudinal members in the front aluminium skeleton of the new  Mercedes-Benz SL-Class provide the resonance space needed for this  arrangement. The loudspeakers are fitted directly in two openings in the  firewall on either side of the footwell. Cavities in the longitudinal  members behind the speakers act as resonating chambers. The outstanding  inherent rigidity of these structural components results in  ultra-precise low notes with extremely little distortion, right up to  very high signal levels. In order words, the new SL features clear,  crisp bass sounds with a high dynamic range as part of its standard  equipment.
The position of these two independent closed woofers in  the footwell permits the creation of ideal acoustic conditions, because  the firewall, the vehicle floor and the underside of the dashboard form  a sort of funnel that focuses and concentrates the sound - a better  sound performance is the result. The acoustic effectiveness improves  significantly. The formula 'low energy plus lots of sound volume' saves  energy on top of it all. This way, the Frontbass system also contributes  towards a CO2 reduction.
Precise, brilliant sound
With  the new Frontbass system, Mercedes-Benz is not only revolutionising  in-car bass sound reproduction - and in particular aboard an open-top  roadster - it is also creating the conditions for exceptional listening  enjoyment. Since the bass loudspeakers now do not need to be installed  in the doors, the disruptive acoustic vibrations typical of this  configuration no longer occur. In addition to this, the sound experts  have placed the mid-range and high-tone loudspeakers in the doors, the  dashboard and in the vehicle rear optimally close to the beltline and  thus almost at the same height as the SL occupants' ears. This way they  produce a precise, brilliant sound quality. The experts speak of an  exact stage reproduction with precise instrument representation and an  equally precise spatial graduation.
Even the standard entry-level  Frontbass system creates a pronounced encircling sound feel and an  emotive sound experience, independently of whether the vehicle roof is  open or closed. As Norbert Niemczyk, responsible for the new Frontbass  system at Mercedes-Benz, explains: "Our objective was not mere sound  volume - although in this respect, too, the system performs amazingly -  but a clear sound instead, one that never becomes "mushy". We have  achieved this. All those who experienced the sound with the Frontbass  system for the first time got out of the car with a big smile on their  face - in-house we call that the Frontbass smile."
Friendly  to the surroundings: focused sound
Acoustic enjoyment of  the highest level is part of the programme in the new Mercedes SL both  with a closed and with an open top. As the Frontbass system focuses the  sound, the powerful sound is concentrated on the vehicle occupants - the  surroundings are significantly less disturbed than is the case with  conventional sound systems. Apart from this, the amplifier automatically  controls the loudspeakers in a different manner depending on whether  the passenger compartment is closed or open, according to the acoustic  conditions, in order to create the best possible sound.
Frontbass  is always on board
The Frontbass concept is the standard  basis in every version of the new Mercedes-Benz SL. In the entry-level  variant it is coupled with an amplifier that is integrated in the COMAND  head unit with an output of 4x25 watts, two Frontbass loudspeakers with  a diameter of 217 mm, two two-way systems for high and mid-range tones  in the doors and two more mid-range speakers in the rear.
The  optionally available Harman Kardon® Logic 7® surround sound system in  conjunction with the Frontbass concept offers a further enhancement and a  musical delicacy of concert hall quality. The heart of the matter is a  Class D amplifier with a total output of 600 W and a digital signal  processor (DSP) for ten audio channels. The two Frontbass loudspeakers  and six two-way systems provide an even more precise and better defined  sound reproduction quality.
Finally, the ultimate in high-calibre  pleasure for the eyes and ears comes courtesy of the high-end  Bang&Olufsen BeoSound AMG sound system, also available as an  optional extra. The Class D ICE power amplifier and the Class D DSP  amplifier with a total output of 900 watts actively control the twelve  high-end loudspeakers via separate channels, thus ensuring the hallmark  B&O crystal-clear sound reproduction. Via the B&O-specific True  Image menu various sound settings such as the true-to-life studio-like  reproduction in reference mode or a space-optimised reproduction in  surround mode can be selected - and the sound fields can be precisely  adjusted to the seats being used. In addition to this, the automatic  volume regulation function Vehicle Noise Compensation automatically  adjusts in accordance with the speed and the exterior and interior  noises measured with a microphone, facilitating exclusive audiophile  high-end sound at all times, irrespective of external influencing  factors such as noises caused by the engine or the airflow.
High-end  music enjoyment with the DVD "Mercedes-Benz Signature Sound"
So  that SL drivers can fully appreciate and enjoy the Surround Sound and  the unique Front Bass system, Mercedes-Benz has edited an exclusive,  limited music DVD with the title "Mercedes-Benz Signature Sound". The  name stands for the unique signature sound of the musical pieces. It  comprises 15 well-known pop/rock songs and 10 masterworks of classical  music, re-worked and fine-tuned to the exceptional acoustic conditions  of the roadster by Grammy-winning experts at one of the best sound  studios in the world. Its transparent, crystal-clear sound provides a  musical experience of the highest level. The DVD "Mercedes-Benz  Signature Sound" can be found in every new SL Roadster that has been  ordered with a Surround Sound system.
Bodyshell tuned to  Frontbass
In order to realise the Frontbass concept, the  sound specialists worked in close cooperation with the bodyshell  designers right from the very first planning stage. A small welcome side  effect is that since the Frontbass concept made the loudspeakers in the  doors superfluous, the designers were able to use the space made free  in the doors for additional stowage compartments.
Infotainment  with internet access, too 
Even in the entry-level  version, the new Mercedes-Benz SL is equipped with the "Cockpit  Management and Data System" COMAND - a car radio and CD/DVD player in  one. The functions also include Bluetooth telephony plus easer operation  of the car telephone. COMAND Online featuring internet access and a DVD  changer is also available as an optional extra.
Both COMAND  versions feature a high-resolution TFT colour display with a 17.8 cm  diagonal (800 x 480 pixels) at the side next to the instrument cluster.  This screen arrangement prevents the driver from being distracted as far  as possible.
Both COMAND variants are operated via what is known  as a "Controller" located on the centre console near the armrest. This  is an optimum ergonomic position for it, and from here it can be  operated easily and safely. The Controller is a very high-quality  turn-and-press actuator with a galvanised surface and can be intuitively  moved in eight directions. Functions can also be activated or confirmed  via rotating and pressing it. A user-friendly new control logic for the  main menus and the sub-menus which can be opened up step by step  enables drivers to leaf through the menus safely and in a targeted  manner.
Even in the entry-level version, COMAND includes the  following features:
- FM radio twin tuner with phase diversity and an additional RDS/TMC tuner for traffic information,
- Entry-level 4 x 25 W audio signal amplifier,
- DVD drive for audio and video,
In  addition, COMAND Online offers
- Six-disc DVD changer
- Internet access
- Integral navigation system with map display (including birdview and a 3D map),
- Integral hard disc for navigation data and additional functions (e.g. music server),
- The LINGUATRONIC voice-operated control system
Both COMAND variants also  support the following components:
- Sound amplifier,
- Media Interface,
- DAB receiver (Digital Audio Broadcast)
- TV receiver (standard-fit in Japan, not available in the USA).
COMAND  Online with a DVD changer
The alternative multimedia  system COMAND Online provides internet access. When the car is  stationary, it enables customers to browse freely in the internet and  quickly access a Mercedes-Benz online service. These integral services  include weather information and a POI search via Google. A route that  has been previously configured on a PC using Google Maps can also be  sent to the car and downloaded in this way.
The fast navigation  function for COMAND Online also has new functions to offer, for example a  3D display with three-dimensional city views. Also new: routes covered  can be recorded and repeated later, specific personal destinations can  be stored or imported via an SD card, plus four alternative routes can  be displayed on the navigation map, including a particularly economical  variant.
The new COMAND Online with a DVD changer offers a 6-disc  DVD changer.
New online services for COMAND Online
Since  the launch of COMAND Online in the new SLK and the facelifted C-Class,  there have been three Mercedes-Benz Apps available to customers
- For calling up weather forecasts and maps,
- For the Local Search from Google, displaying Google Street View images
- Plus Google Panoramio photos, with the option of searching for destinations in the extensive Google archives,
All COMAND Online users also have  access to a Facebook app.
Mercedes-Benz is launching additional  new apps with the new SL: as well as a free news app and a Yelp app (in  the US version only), there are MB Apps for share prices and also a  car-park finder:
- With the news app the user is always kept updated on events. Sorted according to various categories such as financial or sports news, it always finds the latest bulletins from around the world.
- The Yelp app (in the US version only) enables users to search for restaurants from the vehicle. This function uses the social database filled by the Yelp Community. The Yelp app offers a selection according to various restaurant categories within which it is possible to search for the best locations at the current position, at the destination or at a position one chooses.
- The new app which searches for car parks calls up the current occupancy of multi-storey car parks in real time, as well as other information such as opening times and charges. The app supplies data in Germany, Austria and Switzerland. If a suitable parking opportunity has been found, the driver can start the navigation to that destination or call the telephone number stored.
The aerials are no longer  visible
The new Mercedes-Benz SL no longer has any  visible aerials. The aerial structures for the radio and TV reception  are housed in the windscreen. The concomitant aerial amplifiers are  located in the area of the A-pillar. The aerials for are discreetly  integrated in the hybrid boot lid.
New Digital Owner's  Manual
For the first time Mercedes-Benz is equipping the  new SL with a Digital Owner's Manual. The driver can use it to call up  information on operating their vehicle via the COMAND Online system and  view it there on the screen.
The new SL's Digital Owner's Manual  has decisive advantages over a printed version:
- All the information is available immediately.
- It is quick and convenient to search for certain information
- There are various options available for performing a search - by inputting a key word, via the index or via the virtual depiction of a vehicle
Mercedes-Benz  supplements the Digital Owner's Manual for the Mercedes-Benz SL-Class  with a reduced printed edition which contains the fundamental steps for  reliable operation of the vehicle. Not to be forgotten is the fact that  as only around 280 printed pages are included as opposed to more than  580 previously, approximately half a kilo in weight is saved.


 
Some people don't like the redesigned 2013 SL-Class, but I like it.
BalasHapus