Supreme sportiness, style and comfort define the new SL Roadster from Mercedes-Benz, which is available from Mercedes-Benz sales partners from 31 March 2012. Its body and body-in-white have been produced as all-aluminium constructions for the first time. At the market launch, there is a choice of two new powerful 6- and 8-cylinder engines featuring cutting-edge injection technology, with ECO start/stop function as standard. These engines are up to 29 percent more fuel-efficient than their predecessors. Two world-firsts are also being premiered in the new SL – the Frontbass system for the ultimate in listening pleasure even with the roof open and the MAGIC VISION CONTROL wiper/washer system, which applies the water to the windscreen directly from the wiper blade.The new generation of the Mercedes-Benz SL takes the meaning of the famous abbreviation "SL" – super-light – quite literally.Systematic weight reduction is one of the outstanding structural design features of the new SL. Dr Joachim Schmidt, Member of the Management Board of Mercedes-Benz Cars, Sales and Marketing, elaborates: "It was around 60 years ago that we celebrated the successful launch of our first super-light sports car. Since then, every generation of the SL has set new standards. And with the new model we are continuing this tradition."
The new SL sees Mercedes-Benz introducing an all-aluminium body-in-white into volume production for the first time. Together with a host of other intelligent improvements to points of detail, this leads to an overall weight reduction of up to 140 kilograms in comparison to the predecessor model. The aluminium structure is also superior to the predecessor's steel design in terms of rigidity, safety and comfort. "The new SL is the safest roadster in the world!" says Schmidt.
Environmental Certificate for the new Mercedes-Benz SL
The neutral inspectors from the TÜV Süd technical inspection authority have confirmed the high environmental compatibility of the new Mercedes-Benz SL in good time for the market launch, duly awarding the sporty and stylish Roadster the Environmental Certificate in accordance with ISO standard TR 14062. This certification is based on an exemplary life-cycle assessment for the SL, which entailed a comprehensive analysis of the Roadster's environmental impact throughout its entire life cycle – from production through extensive service to recycling at the end of its life.The results make good reading: the new SL-Class reveals advantages over the previous model in all impact categories. Primary energy requirements have been reduced by 23% and NOx emissions by 16% over the entire life cycle, for example. In addition, the new SL incorporates a higher percentage of high-quality recyclates and renewable raw materials. For the first time in automotive engineering, a secondary alloy has been qualified for aluminium inner panels in the body-in-white, in order to minimise the environmental impact in the manufacturing process. This goes far beyond the legal requirements. The Environmental Certificate and supplementary information are made available to the public in the "Life Cycle" documentation series, which is retrievable at http://www.mercedes-benz.com . In addition to the SL, the models of the A-, B-, C-, E-, M- and S-Class, the GLK, the SLK and the CLS have also received the Environmental Certificate from TÜV Süd.
Prices in Germany for the new Mercedes-Benz SL incl.19 % VAT:
- SL 350 93,534 euros
- SL 500 117,096 euros
Credits: Daimler AG Copyright © 2012, Mercedes-Benz-Blog. All rights reserved.
Under the slogan "The new SL. Athlete. Esthete.", Mercedes-Benz starts on 12th March 2012 the media campaign for the sixth generation of its legendary luxury sports car. Various print ads in elegant monochrome look and an unusual TV ad in black and white starring Boris Becker put the key message in the spotlight: the SL is the perfect epitome of cultivated sportiness. Check out the new SL-Class advertisement >> HERE
"The new campaign focuses on what the new SL is: the perfect fusion between a luxury coupe and a dynamic sports roadster," says Anders Sundt Jensen, Vice President Brand Communications at Mercedes-Benz Cars. "No other vehicle has reached a cult status as the SL and the new generation is even more convincing as a synthesis of exquisite comfort, refined sportiness and fascinating open-air driving pleasure."
The 44-second TV spot "Voice-over" is a humorous approach to the extraordinary performance of the new SL. The focus is on the all-aluminum body, which gives the premium roadster unparalleled dynamism and a significant decrease in the overall weight compared to its predecessor. As a passenger, Boris Becker enjoys the ride on a winding coastal road. Full of enthusiasm, he counts out loud the technical highlights of the SL: "V8 Biturbo, ..., from 0 to 100 in just 4.6 seconds, ..., full-aluminum body, 125 kilograms lighter than its predecessor" Annoyed, the driver slams on the brakes and invites the tennis legend to get out of the car. Surprised, Becker looks after the roaring SL and notes enviously: "And now, another 90 kilograms lighter...".
The focus of the print ads is the combination of luxury and feeling roadster, which is highlighted by the monochrome-look campaign in a particular way. Various motifs direct the SL in an urban environment, mediated by the photographic perspective which denotes vastness and pleasure to drive. Both the vehicle and the environment are uniformly decorated in fine silver gray, broken only by the red tail lights, black-tinted windows and a yellow element in the urban architecture.
Another component of the communication campaign is the SL Bodywork app, which will be available for download starting end of March, after the market launch of the luxury roadster, on www.mercedes-benz.com/sl, in the App Store and Android Market. The app offers the user, independent of time and place, a personalized fitness training programme in the areas of strength, endurance and stability.
The campaign was developed by the creative agency Jung von Matt / Alster and Jung von Matt / Spree. The TV spot was produced by Radical Media and directed by Christian Alby. Igor Panitz was the photographer of the print ads.
Credits: Daimler AG
Copyright © 2012, Mercedes-Benz-Blog. All rights reserved.
The seventh generation of the SL-Class leads into the future a prestigious history that began 60 years ago. The R 231 model series makes its entrance in the automotive world as the most refined and sophisticated roadster in its class. The Sport Leicht now boasts an a lightweight aluminium construction, a very aerodynamic design, powerfully efficient V6 and V8 engines with BlueDIRECT technology, an unprecedented level of safety, state-of-the-art equipment and technology and the traditional, all so famous Mercedes-Benz luxurious style. Learn more essential facts about the new SL by following the next links:
1. The new Mercedes-Benz SL: Lightweight, athletic, luxurious
2. The new Mercedes-Benz SL: Model range - Essence of refined sportiness
3. The new Mercedes-Benz SL: Equipment - Safer, more convenient, more individual
4. The new Mercedes-Benz SL: Statements - Quotations on the new SL
5. The new Mercedes-Benz SL: Design - Masculine, muscular athlete’s physique
6. The new Mercedes-Benz SL: Interior and appointments - Luxurious comfort and sporty precision
7. The new Mercedes-Benz SL: Body and bodyshell - Aluminium comes up trumps
8. The new Mercedes-Benz SL: Lightweight construction under the microscope - Progress in detail
9. The new Mercedes-Benz SL: MAGIC VISION CONTROL adaptive windscreen washing system - Visibility as if by magic
10. The new Mercedes-Benz SL: Aerodynamics - Breezy, but never bothersome
11. The new Mercedes-Benz SL: Engine and drive system - The power and the economy
12. The new Mercedes-Benz SL: Chassis and suspension - Best contact with the road
13. The new Mercedes-Benz SL: Optional equipment - AMG Sports package
14. The new Mercedes-Benz SL: Safety - Top technology for the greatest possible safety
15. The new Mercedes-Benz SL: Infotainment - The fully integral sound of tomorrow
16. The new Mercedes-Benz SL: 60 years of SL history - From generation to generation
Copyright © 2012, Mercedes-Benz-Blog. All rights reserved.
At the same time the combination of the letters “SL” became a phenomenon. As an abbreviation of “super” and “light” it had originally merely been intended to differentiate between the 300 and 300 S models, but it soon took on a charismatic shine. The forefather of the race track was followed by the first descendant available for purchase in 1954: the 300 SL series-production sports car (W 198), which achieved equal renown and was known as the “gullwing” model on account of its unusual doors. Ever since, the two letters have stood for unique cars, for legendary sports cars. The irresistible design, the superb engineering and the virtually unlimited motoring pleasure they bring have bestowed on the Mercedes-Benz SL an aura which has elevated all the models created since 1954 to the status of classic, one after the other. Amongst automotive enthusiasts they are highly sought-after collectors’ vehicles and pass on their special status from generation to generation. It is no wonder, then, that the 300 SL gullwing model was voted “Sports Car of the Century” by a jury consisting of motoring journalists in 1999.
To mark its sixtieth birthday, Mercedes-Benz has completely assembled the 1952 racing car with the vehicle identification number 2 again – true to its original state and in such a way that it is ready to drive. Countless hours of work, a great deal of sweat and know-how have been invested by the specialists at Mercedes-Benz Classic in the car’s restoration. In so doing they went to enormous lengths to ensure that the vehicle was not “over-restored” and that instead it would retain its individual patina which makes its unique character shine. On the occasion of the unveiling of the new SL, the forefather – bathed in authentic splendour – was also presented to the public and demonstrated the fountainhead of the SL legend. In this juxtaposition the two SL models from 1952 and 2012 represented the entire spectrum of the SL legend – spanning from its origins right through to the current pinnacle.
But 60 years ago it was not just the SL bloodline that was born; at the same time the foundations for the entire Mercedes-Benz sports car family were laid – and today, encompassing the SL, the SLK and the SLS AMG, it is more strongly differentiated than ever before. Even back in the 1950s, when the successful racing car evolved into a series-production car available for purchase, Mercedes-Benz offered not just the decidedly sporty 300 SL “Gullwing” but a second SL model, too: the less powerful yet equally fascinating 190 SL, which, in its capacity as the “little brother” of the gullwing model, opened up the opportunity to experience the SL legend to a larger circle of customers.
In the present day the 190 SL is often regarded as the predecessor of the compact SLK, whilst the 300 SL gullwing model with its characteristic doors and its outstanding performance potential is widely perceived as the ancestor of the SLS AMG. Both models, the 300 SL and the 190 SL, are, however, first and foremost precisely what is revealed by the model lettering on the boot lid: the roots of the legendary SL ancestral line, which stands for refined sportiness like no other has done for over six decades now.
The cars in this model series were created with their own unique characteristics because their time had come, because Mercedes-Benz was meeting its customers’ requirements. This also applies to the subsequent SL generations – each one reflects the spirit of its day and the wishes and desires of their buyers. The sales success of every single SL generation proves Mercedes-Benz has always built the SL which was best suited to its time – having said that, they generally tended to be somewhat ahead of their time in Stuttgart, setting new trends. This is why comfort, which, alongside sportiness, can be seen as the inherent discipline of the SL models, became an indispensable part of the SL philosophy very early on. Further hallmark SL characteristics spanning the generations include superior performance, technical innovations and, of course, an exciting, often surprising, design which always finds new ways of succinctly expressing the high emotional appeal of the SL models.
1954 – 1963: W 198 – the legend enters series production
Without a doubt the 300 SL racing car of 1952 was the primal concept. With an enhanced design and boasting refined ride comfort in spite of its higher output, it was continued as a series-production sports car. In 1954 the 300 SL gullwing model embarked on an incomparable triumphal procession. Alongside the gullwing doors, its other characteristic features were the filigree space frame familiar from the racing car and also the first four-stroke engine with petrol injection in a series-production passenger car. It had an output which was sensational in its day: 215 hp from a displacement of three litres. From 1957 the 300 SL was then built exclusively as an open-top version.
An open-top model right from the outset, the 190 SL was presented to the public at the same time as the 300 SL. Its roots lay in proven series-production technology rather than in the world of racing. Yet this did not impact on the fascination surrounding the vehicle – on the contrary: that special SL feel was now available for a significantly larger group of buyers to experience. In eight years nearly 26,000 vehicles found proud owners.
“The 300 SL belongs to the genus of cars which challenge their drivers and at the same time give them enormous driving pleasure.”
Juan Manuel Fangio, five times Formula 1 world champion
1963 – 1971: W 113 – the “Pagoda”
In the spring of 1963, when Mercedes-Benz ceased production of the 300 SL and 190 SL, the joint successor was an SL model which caused a furore – above all because of its unusual exterior. As well as the fresh, new lines, the dominating design feature was a removable coupé roof, which sloped down to the centre of the vehicle. This was unique, and reminiscent of Far Eastern temple architecture, resulting in this SL being referred to colloquially as the “Pagoda”.
“In the many years I have been driving, I cannot remember wanting to own any car I have ever driven (with the exception of racing cars!) as much as this one.”
Formula 1 racing driver and Mille Miglia winner Stirling Moss in a letter to
the Head of Racing, Alfred Neubauer
1971 – 1989: R 107 – the evergreen
In 1971, the “Pagoda” model was then followed by an SL model series which was destined to be built for 18 years. The advanced styling of this classic ensured that it has continued to look contemporary to this day. Known internally as the R 107, this roadster’s combination of distinctive curves and clean, frill-free lines still gives it a handsome and iconic appearance.
The R 107 was the first SL generation to be characterised by a large variety of models. During its long construction period, it was available, for instance, with engines from the 2.8-litre six-cylinder in-line engine to the 5.6-litre V8. Over a long period of time the customer was able to choose from three engines. And the R 107 set new standards in safety with its high safety reserves and numerous innovative, detailed solutions.
“It’s powerful, yet not ostentatious. It simply oozes superiority and masculinity.”
Hans Hermann, Formula-1 racing driver and Le-Mans winner
1989 – 2001: R 129 – the sculpture with style
In 1989 the last of 237,287 SL Roadsters of the model series R 107 rolled off the assembly line in Sindelfingen, to be succeeded by the SL model series known internally as the R 129. Its defining wedge shape immediately found popularity, radiating taste and style. Today it is thought of as an automotive sculpture.
In addition to design quality of the highest calibre and maximum open-air motoring pleasure, this SL offered occupant protection on an uncompromisingly high level. Its safety features included, for example, a roll-over bar which automatically extends in critical situations and – for the first time anywhere in the world – what is known as an integral seat with a three-point seat belt integrated into the seat. The R 129 also raised the bar when it came to its engine line-up – featuring units with up to twelve cylinders – and its driving characteristics.
“I bought the SL because I believe it to be the finest car in the world.”
José Carreras, star tenor and automotive enthusiast
2001 – 2012: R 230 – a stylish synthesis of tradition and modernity
With a stylistically fascinating and technically discerning sports car in the model series R 230, Mercedes-Benz continued the long SL tradition in the autumn of 2001. It was the first SL to be fitted with a vario-roof. The innovative roof construction, which transforms the two-seater roadster into a weatherproof coupé (or vice versa) within a few seconds, was launched by Mercedes-Benz in 1996 in the first-generation SLK, and enhanced for the SL. The R 230 also offers the active suspension system Active Body Control (ABC), a unique package comprising state-of-the art electronic control systems and optimised occupant protection. But the R 230 also stands for new performance dimensions and outstanding sportiness: as the SL 55 AMG, which was used in 2001 and 2002 as the official Safety Car in Formula 1, it exceeds the 368 kW/500 hp mark. When it was unveiled in 2004, the SL 65 AMG was no less than the most torquey roadster in the world, and in 2008 and 2009 the R 230 once again took on the role of the Formula 1 Safety Car – this time as the SL 63 AMG.
"With regard to the balancing act between comfort and sportiness, the SL is now setting new benchmarks"
Wolfgang König, automotive journalist in the 2001 road test
As of 2012: R 231 – athlete and aesthete
The new SL is now taking on the original SL, as demonstrated objectively by its performance data and subjectively by its driving feel. Along with the S-Class and the E-Class, the SL belongs to the Mercedes-Benz model series with the longest tradition. And like virtually no other vehicle class from Mercedes-Benz it stands for fascination and emotion.
Credits: Daimler AG
Copyright © 2012, Mercedes-Benz-Blog. All rights reserved.
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 SL 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 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 the telephone and GPS/Navigation 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 SL 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.
Credits: Daimler AG
Copyright © 2012, Mercedes-Benz-Blog. All rights reserved.
“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 SL 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 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.
Credits: Daimler AG
Copyright © 2012, Mercedes-Benz-Blog. All rights reserved.
The AMG Sports package available as an option renders the SL even more dynamic. It comprises: Exterior:- Front and rear skirts as well as side skirts in an AMG design
- 19-inch AMG 8.5 J x 19 light-alloy wheels with 255/35-sized tyres at the front, and 9.5 x 19 wheels with 285/30 tyres at the rear
Technology:
- A sports suspension lowered by ten millimetres if the ABC suspension is not fitted
- Perforated rear brake discs; all brake callipers are more eye-catching with the “Mercedes-Benz” lettering
- Larger braking system from the V8 also for the V6
- Special S shift identification
Interior:
- Seats with a special vertical piping design, covered with perforated black leather
- Steering wheel, covered with black leather in the area of grip, with
silver-coloured shift paddles
- Contrasting topstitching on the seats, steering wheel, dashboard, door trim and centre console
- Trim parts in black haematite
- AMG floor mats made of black velour with the AMG logo
- Door trim with perforated leather
- Instruments with a start/finish chequered flag design
Credits: Daimler AG
Copyright © 2012, Mercedes-Benz-Blog. All rights reserved.
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 SL 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 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 SL 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 SL 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.
Brake disc dimensions
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 SL 350 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 SL 500 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).
Credits: Daimler AG
Copyright © 2012, Mercedes-Benz-Blog. All rights reserved.
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 SL 350 covers this sprint in 5.9 seconds, which is three tenths faster than its predecessor. From a standstill the SL 500 races to the 100 km/h mark in 4.6 seconds, making it eight tenths faster than the previous SL 500.
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 SL 350 and 3.2 seconds for the SL 500 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.
The key data for the new SL
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 SL 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.
Credits: Daimler AG
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