AMG Performance Studio and designo
Even more exclusivity ex factory
• AMG light-alloy wheels in two attractive colour variants
• AMG Handling package for even greater driving dynamics
• designo range to meet all requirements
• “Edition 1” for those with the most discerning of tastes
Optionally the SLK 55 AMG can be fitted out with even more exclusive appointments ex factory. Tailor-made individuality is guaranteed thanks to the AMG Performance Studio and designo ranges. Items available exclusively for the SLK 55 AMG from the AMG Performance Studio include:
• AMG multi-spoke light-alloy wheels, painted in titanium grey with a high-gloss finish, with 235/40 R 18 (front) and 255/35 R 18 (rear) tyres
• AMG multi-spoke light-alloy wheels, painted in matt black with a high-gloss finish on the rim flange, with 235/40 R 18 (front) and 255/35 R 18 (rear) tyres
• AMG Handling package (AMG Performance suspension, AMG rear axle differential lock, composite brake discs on the front axle, AMG Performance steering wheel in nappa leather/Alcantara®)
• AMG Performance steering wheel in nappa leather/Alcantara®
• AMG door sill panels, illuminated in white using LED technology
• AMG floor mats
• AMG Driver’s package (top speed restriction increased to 280 km/h, attendance of driver training course at the AMG Driving Academy)
designo range to meet all requirements
Designed to meet the needs of those with more individual tastes are the optional appointments “designo leather” and “designo Exclusive leather”, offering eleven single-tone and ten two-tone upholstery variants. In the case
of designo Exclusive leather, not only are the AMG sports seats, door centre panels, door armrests, centre console and handrest finished in designo leather, but the upper part of the dashboard and door beltlines also come in black nappa leather. Both variants also include designo velour floor mats as well as a selector lever in black nappa leather and colour-coordinated double stitching on the leather upholstery.
Available matching elements include designo trim in “AMG carbon fibre” and “black piano lacquer” for the centre console. The windscreen frame in designo Alcantara® anthracite, seat belts in silver or red and also five attractive designo paint finishes – including two matt paint finishes – round off the stylish appearance perfectly.
For those with very special tastes: the SLK 55 AMG “Edition 1”
Similar to the C 63 AMG Coupé and CLS 63 AMG, a particularly appealing complete package is also available in the guise of the SLK 55 AMG “Edition 1”. This model variant features a whole host of specially designed high-quality exterior and interior details. There are three different paint finishes to choose from: designo magno cashmere white, diamond white metallic BRIGHT and obsidian black metallic. To add that perfect touch to the overall appearance there are also multi-spoke AMG light-alloy wheels painted in matt black with a high-gloss finish on the rim flange.
To match the exterior design, the interior of the Edition 1 is available exclusively in two-tone “designo Exclusive leather” in platinum white pearl. The windscreen frame in Alcantara®, AMG carbon-fibre trim, the AMG Performance steering wheel with Alcantara® inserts in the grip areas as well as white illuminated AMG door sill panels all help to create some attractive contrasts. Further visual highlights include platinum white contrasting stitching for the upper part of the dashboard, the door beltlines, the AMG Performance steering wheel and the shift lever gaiter, as well as a roll-over bar finished in designo platinum white pearl leather.
Design and equipment
Dynamic and exclusive – characteristically AMG
• Exterior and interior style elements of the SLS AMG Roadster
• High-quality materials finished with an eye for detail
• Comprehensive standard equipment, exclusive optional extras
• Optional COMAND Online with internet access
Powerful, dynamic and unmistakable – the SLK 55 AMG’s unique high-tech package and high performance levels are already apparent even when the vehicle is at a standstill. Visually, it is clear that the top-of-the-range V8
SLK model has been inspired by the SLS AMG Roadster: the wide radiator grille with large, centrally-positioned star and wing-shaped slats, as well the vent grille with chrome fins in the front wings, are all reminiscent of the super sports car. At the same time, both style elements also hark back to the famous Mercedes-Benz 300 SL Roadster from 1957.
The unique AMG bodystyling comprises a distinctive front apron with a lower cross strut painted in a high-gloss black finish. Large air inlets help to ensure a reliable air flow over cooling areas. The outer cooling-air openings also house the AMG-specific LED daytime driving lights.
A lasting impression is also left by the clear glass headlamps with their darkened reflectors. The optional Intelligent Light System (ILS) provides five lighting functions (cornering light function, country mode, motorway mode, active light function and enhanced fog lamps), which are activated depending on the driving conditions. When this is fitted, the main headlamps are twin-tube units, and the indicators and position lights feature LED technology.
When viewed from the side, the “V8 AMG” lettering beneath the air vent is immediately apparent. Dynamically designed AMG light-alloy wheels, featuring a five-spoke design and painted in titanium grey with a high-sheen finish, also provide an additional sporty highlight. Two additional design variants are also available optionally for the SLK 55 AMG from the AMG Performance Studio: four-spoke AMG light-alloy wheels, painted either in titanium grey or matt black.
Other features of the AMG bodystyling include the distinctively shaped side sill panels, as well as the unique rear apron. With its expressive shape, it highlights the width of the vehicle. The black diffuser insert with three deeply contoured fins also adds to the striking visual appearance, as do the two chrome twin tailpipes of the AMG sports exhaust system with exhaust flaps.
Further characteristic AMG features come in the form of the darkened LED bicolour tail lamps, as well as the AMG spoiler lip on the boot lid. Finished in the vehicle body colour, it helps to reduce lift at the rear axle and thus contributes to driving stability, particularly at high speeds.
Interior: quality, precision and style
The dynamic and stylish character continues seamlessly into the interior of the vehicle. Providing an impressive look and feel, the interior of the SLK 55 AMG welcomes its occupants with a sense of precision which is reflected in the workmanship and the high-quality finishes of the materials used. The cockpit too, which has been finished with a great eye for detail, boasts numerous style elements from the SLS AMG Roadster: for example the four air vents, which evoke associations with jet engines, and the centre console which is made of solid, brushed aluminium.
Both style elements are integrated harmoniously into the wide dashboard. As an optional extra, the interior can be exclusively enhanced with the addition of an analogue clock, positioned centrally and featuring an IWC design. Steeped in tradition, Swiss watch manufacturer IWC is a cooperation partner of AMG, together with Italian motorcycle brand Ducati.
Also integrated harmoniously into the interior is the AMG instrument cluster featuring a sporty design with two dial-type gauges. It boasts uniquely designed dials with red indicator needles, a 320 km/h graduated scale and also AMG and V8 lettering. Just like other AMG high-performance vehicles, the SLK 55 AMG keeps its driver informed by means of the AMG main menu. Three modes are available: “Warm Up”, “Set Up” and “RACE”. “Warm Up” shows the engine oil and coolant temperatures as well as the current status of the ECO start/stop function. “Set Up” provides information on the current ESP® mode and the transmission mode “C”, “S” or “M”. In “RACE” mode, the RACETIMER becomes available: the driver can use this feature to record lap times when driving on a closed-off race track.
An interior highlight: the AMG Performance steering wheel
The AMG main menu is operated using the multifunction buttons on the AMG Performance steering wheel, which is finished in nappa leather. The specially shaped steering wheel rim features flattened top and bottom sections, as well as grip areas covered in perforated leather to help ensure optimum vehicle control. One particular visual highlight is the metallic trim, surrounding the three-dimensional airbag cover on the three-spoke steering wheel, the lower spoke of which has an open design. Aluminium shift paddles make manual gear changes a pleasure, while the button to configure transmission modes “C”, “S” or “M” is located within easy reach in the centre console.
The AMG sports seats offer high levels of comfort on long journeys and excellent lateral support, and come with a distinctive transverse stitch design as well as AMG badges: the upholstery combination ARTICO man-made leather/black fabric comes as standard, or alternatively the interior of the SLK 55 AMG can be enhanced with sun-reflective nappa leather, Exclusive nappa leather and designo leather. Outstanding occupant safety comes courtesy of the height-adjustable, crash-responsive head restraints which are integrated into the seat backrests.
Innovative optional extras: AIRSCARF and AIRGUIDE
Drivers looking to extend the roadster season can also choose the optional AIRSCARF neck-level heating system. Warm air from vents in the head restraints flows around the head and neck area of the vehicle occupants. To reduce draughts when driving with the top down, the SLK 55 AMG can also be fitted with a draught-stop. This consists of a net in a fixed frame which is mounted between the head restraints. When not in use, it can be stored in the luggage compartment to save space.
A comfortable alternative to the draught-stop is a new pivoting draught-stop, AIRGUIDE. It consists of pivoting transparent plastic layers which are attached to the reverse of the roll-over bars. This is the world’s first draught protection system that enables different comfort levels to be selected for two occupants, as the driver and passenger can individually pivot the units to the centre of the vehicle in a flash, thus taming turbulent air flow from the rear. Advantage: no installation or removal effort required.
Ground-breaking: a choice of two navigation systems
As an alternative to the standard basic Audio 20 CD radio, there is also a choice of the Becker® MAP PILOT entry-level navigation package as well as the COMAND Online system. The Becker® MAP PILOT, which can also be retrofitted, makes a low-cost navigation function available for the entry-level Audio 20 CD radio. Its advantages over aftermarket solutions include integrated operation via the central controls and the Audio 20 display, a concealed location in the glove compartment and updating via an internet portal.
Networked: COMAND Online with internet access
The COMAND Online multimedia system now offers internet access for the first time in the SLK too. Customers can either surf freely on the internet when at a standstill or to a Mercedes-Benz online service while driving; the latter’s pages can be called up particularly quickly and it is simple to operate. The integral services planned include Google™ Local Search and further online services from other suppliers such as the weather. It is also possible to send individual destinations and routes to the vehicle via Google Maps. More Mercedes-Benz online services will be introduced gradually and then all customers will be able to use them.
The high-resolution colour display measures 17.8 cm. Photos can be shown on the large screen and turned over manually, as in a slide show. Where the audio equipment is concerned, too, new types of representation bring a fresh look and more convenient operation. The new Cover Flow function, for instance, sorts the title images of the music albums stored in a carousel-like form, so that the driver can easily leaf through their music collection – even if it is rather on the large side: the memory for compressed audio files (MP3, WMA and AAC formats) now comprises as much as 10 GB. As an option COMAND Online is available with a 6-disc DVD changer.
The ultimate in convenience is afforded by the Music Search function, which enables drivers and passengers to search the hard disc, SD memory cards, USB sticks, CDs and DVDs for specific music tracks and artists. The search can be according to various criteria, for instance artist, album or genre. If a name needs to be entered, the software will also tolerate spelling mistakes. The driver is therefore able to devote their full attention to the traffic. As a further advantage, the occupants are able to search all the connected media and devices simultaneously.
Up-to-date maps of Europe are provided without charge for three years
The fast hard-disc navigation system of COMAND Online also has added functions. New features include a 3D display with three-dimensional city views. Also new: routes covered can be recorded and repeated later, specific personal destinations can be imported via an SD card and four alternative routes can be displayed on the navigation map, one of them a particularly economical variation. Mercedes-Benz customers in Europe receive the current cards for their COMAND Online multimedia system free of charge for three years. Authorised Mercedes-Benz dealers upload the updates for navigation data in 39 European countries into the navigation system when the customer visits their premises.
In Europe COMAND Online also comprises the Speed Limit Assist, which receives its information for traffic sign recognition via a camera and navigation database. COMAND Online also includes the LINGUATRONIC voice-operated control system for audio, telephone and navigation. The new “One Shot” input for the navigation is particularly convenient, whereby the place and road can be said directly after one another.
Overview of the standard equipment of the SLK 55 AMG (selection):
• AMG door sills in brushed stainless steel
• Audio 20 CD radio with double tuner, colour display, Bluetooth® interface, hands-free function and USB interface
• Headlamp Assist
• Remote boot lid unlocking
• Air conditioning
• Tyre pressure loss warning system
• Sports pedals in brushed stainless steel, with rubber studs
• Cruise control with SPEEDTRONIC variable speed limiter
• Vario-roof painted in vehicle colour, operated electrohydraulically
• Selector lever and shift lever gaiter in nappa leather
Optional extras include (selection):
• Ambient lighting with “solar red” colour tone
• DAB tuner (Digital Audio Broadcasting)
• DISTRONIC PLUS including PRE-SAFE® Brake
• Speed Limit Assist
• Intelligent Light System (ILS) with bi-xenon lights
• THERMOTRONIC automatic climate control
• Media interface
• Memory package incl. electrically adjustable front seats, steering column and exterior mirrors with memory function as well as 4-way lumbar support for driver and passenger
• PARKTRONIC with Parking Guidance
• Heated seats
• High-gloss black ash trim
• High-gloss dark brown burr walnut trim
Bodyshell and safety
Exemplary protection Mercedes-style
• Vario-roof opens and closes in under 20 seconds
• Optional panoramic vario-roof with MAGIC SKY CONTROL
• New headbag and crash-responsive head restraints
• ATTENTION ASSIST and active bonnet as standard
• DISTRONIC PLUS and PRE-SAFE® Brake available as optional extras
In 1996, precisely 15 years ago, Mercedes-Benz presented the first generation of the SLK, which amazed automotive experts with its exceptional vario-roof.
To this day, the Stuttgart-based automotive manufacturer has remained true to this technology which provides unrivalled levels of convenience and safety for motorists. The standard vario-roof on the current SLK 55 AMG opens and closes in less than 20 seconds, transforming the open-top roadster into a closed-top coupé with rigid roof at the touch of a button.
Alternatively, a panoramic vario-roof in tinted polycarbonate can also be chosen. The third variant is a world premiere – 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 frames of the three roof variants are made of magnesium. This makes each roof around six kilograms lighter than in the previous model, giving the car a lower centre of gravity – which benefits its agility. As an optional extra, a convenience opening feature is also available for the vario-roof: all it takes is a press of a button on the vehicle key to open the roof conveniently from outside the vehicle. The luggage compartment capacity with the vario-roof closed is 335 litres. When the roof is opened, the capacity is reduced by 110 to
Leading position thanks to Real Life Safety philosophy
The SLK 55 AMG also enjoys a leading position when it comes to active and passive safety too. As is usual at Mercedes-Benz, its safety concept is based on real-life accident research – Real Life Safety is the philosophy developed by the Mercedes safety experts. It forms the solid basis on which the engineers have developed or implemented most of the modern assistance systems which today not only effectively support drivers, but have also been adopted by a great number of competitors.
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 forming part of the standard equipment are crash-responsive head restraints. They improve occupant protection and as such help to reduce the risk of whiplash. In the event of a rear impact, the head restraints can be pushed around 40 mm forwards and 30 mm upwards, thus supporting the heads of the vehicle occupants earlier.
DISTRONIC PLUS and PRE-SAFE® Brake enhance safety
Available as optional extras are the DISTRONIC PLUS proximity control as well as PRE-SAFE® Brake, already tried and tested in other Mercedes-Benz models. Both systems work in conjunction 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 automatically adjusts the distance to the vehicle in front. If necessary,
it can apply the brakes, even bringing the SLK 55 AMG 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 audible warnings, thereby prompting the driver to take action, at which point he is also supported by Brake Assist 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 PRE-SAFE® Brake in preparation for autonomous braking. This happens in two stages:
• Around 1.6 seconds before the calculated impact point the system decelerates the car 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 system.
• 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 its speed is below 70 km/h.
Even more safety and comfort available as an option
Those wishing to do so can extend the range of assistance systems in the new SLK even further with the addition of features enhancing both safety and comfort:
• The Intelligent Light System provides five lighting functions (cornering light function, country mode, motorway mode, active light function and enhanced fog lamps), which are activated depending on the driving conditions
• Speed Limit Assist is able to detect speed limit signs using a camera on the inside of the windscreen, and indicate the detected speed limit in the instrument cluster or central display.
• The optional PARKTRONIC incl. Parking Guidance supports the driver when parking. Its ultrasonic sensors measure the length of parking spaces as the car drives past; the cockpit display then provides a schematic representation of the recommended parking manoeuvre.
Only available from Mercedes-Benz – the anticipatory occupant protection system PRE-SAFE®
An additional safety highlight available in the new SLK 55 AMG is the anticipatory occupant protection system PRE-SAFE®, a system developed by Mercedes-Benz which is unique throughout the world. If the system detects
an acute risk of an accident, it reflexively activates precautionary protective measures for the vehicle occupants, so that the seat belts and airbags are able to fulfil 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. This highly effective system has so far not been taken into account when producing ratings, however.
Additional post-crash measures supplement the PRE-SAFE® system to enable prompt assistance after an accident has occurred: depending on the damage,
the interior lighting can be switched on automatically, the side windows can be opened by 50 mm to provide better ventilation in the interior, and in vehicles with the Memory package the steering wheel can be moved upwards.
Taking into account all of the requirements of the rating institutes
In developing the SLK, the requirements of Euro NCAP as well as all global consumer ratings were also taken into account. Forming the basis for this is the vehicle’s body structure, which follows tried-and-tested concepts and has also been enhanced in a number of details. These include strengthened supports, a new structure for side impacts and a new fibre-reinforced roll-over bar. In the event of an accident, up-front sensors and lateral satellite and roll-over sensors help the central control unit to predict the nature and severity of the accident. New, additional pressure sensors in the doors as well as acceleration sensors in the
front bumper help in detecting an impact with a pedestrian.
The restraint systems with two-stage driver and front passenger airbags have also been enhanced. A new feature is the headbag, which provides generous lateral protection for the head impact area. An additional thorax airbag in the seat backrest protects the upper body in the event of a side impact. The seat belts, with belt buckle tensioners and speed-sensitive belt force limiters, serve to highlight the high safety standards of Mercedes-Benz. Automatic child seat recognition also comes as standard.
Pedestrian protection courtesy of the active bonnet
The SLK 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 active bonnet is immediately raised by 85 mm. 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 the pedestrian during the impact, thus reducing the overall risk of injury.
As a result, the new SLK 55 AMG provides its occupants not only with a superior level of safety in all areas – something which is unique in this segment – but also enhanced safety for other road users too.
Chassis and braking system
Driving dynamics at the highest level
• Specific AMG sports suspension with aluminium hub carriers
• Direct-Steer system enhances agility and comfort
• AMG high-performance braking system and Torque Vectoring Brake
• 3-stage ESP® with customised control strategy
• Optional AMG Handling package available
To ensure optimum wheel control, the SLK 55 AMG features three-link front suspension and multi-link independent rear suspension. Forged aluminium hub carriers reduce the unsprung masses, which benefits both the road feel and response of the spring assemblies. The AMG sports suspension, specifically tuned for high performance, comprises independent suspension struts with stiffer spring/damper tuning. In combination with all-round stabilisers with a larger diameter, more rigid torque strut bearings on the front axle as well as a more negative camber on the rear axle, the SLK 55 AMG impresses with neutral understeer/oversteer characteristics, high cornering speeds and a low body roll in fast S-shaped bends.
Yet the top-of-the-range SLK model from AMG boasts not only a highly dynamic driving style but also comfortable cruising thanks to the comfort on long journeys which is characteristic of a Mercedes. The AMG light-alloy wheels measuring 8 x 18 (front) and 9 x 18 (rear) are fitted with 235/40 R 18 and 255/35 R 18-sized wide-base tyres.
Innovative: Torque Vectoring Brake and Direct-Steer system
To increase agility and lateral dynamics even further, the SLK 55 AMG comes fitted with the Torque Vectoring Brake and Direct-Steer system as standard. The Torque Vectoring Brake is able to detect a tendency to understeer and generates a defined rotational movement of the vehicle about the vertical axis.
This is made possible thanks to targeted braking intervention, within fractions of a second, by the Electronic Stability Program ESP® on the inside rear wheel when cornering.
This results in the SLK 55 AMG steering into the bend precisely and under full control, without any loss of handling dynamics. This system is complemented perfectly by the AMG Direct-Steer system: compared with standard steering, it increases handling and agility, enhances safety at higher speeds, such as on motorways, thanks to a greater steering effort being required, and at the same time also reduces the physical effort required when parking.
The ratio is 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 increases 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. The increase in driving dynamics is also aided by an increased yaw rate (steering response) at low to medium speeds, as this augments the effect of the steering movement. At high speeds this increase in yaw rate is small, which means that the car responds safely and predictably to steering movements.
Despite its remarkable effect, the key component of the Direct-Steer system is a tried-and-tested 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.
Power steering pump reduces consumption
A newly developed power steering pump helps to reduce fuel consumption.
The power assistance for the steering only requires energy when the driver is actually steering. In addition, the AMG Direct-Steer system has a parameter function adapted to match the characteristics of the AMG sports suspension. This results in optimum response from the central position, outstanding road feel and dynamic handling in all driving situations.
3-stage ESP® system with “SPORT Handling Mode”
A special feature exclusive to AMG is the 3-stage ESP® system. It enables individual control strategies to be selected at the touch of a button: using
the ESP® button in the centre console, the driver is able to choose between “ESP ON”, “SPORT Handling Mode” and “ESP OFF”. The currently active mode is shown in the display of the AMG instrument cluster. In “ESP ON” mode, braking intervention on one or more wheels and a reduction in engine torque occur if the car starts to become unstable.
Briefly pressing the ESP® key activates “SPORT Handling Mode”. By means of over/understeer intervention accompanied by engine torque adjustment, this mode allows even more dynamic handling manoeuvres such as the appropriate drift angles. All the functions of ESP® are available as soon as the brake pedal is depressed.
Sustained pressure on the ESP® key activates “ESP OFF”. In this case there
is no dynamic control intervention whatsoever, and the engine torque is no longer reduced. “ESP OFF” should only be used by highly experienced drivers on closed racetracks. In this mode too, all the functions of ESP® are available as soon as the brake pedal is depressed. In all three ESP® modes the traction logic of the acceleration skid control (ASR) is active. As soon as a drive wheel begins to spin, traction is significantly improved by specific braking intervention.
Powerful AMG high-performance braking system
The AMG high-performance brake system is characterised by outstanding responsiveness, short stopping distances and excellent fatigue strength. The ventilated and perforated brake discs on all wheels are decelerated by means of
4-piston fixed callipers (front) and 1-piston floating callipers (rear), respectively. A new addition is the electrically operated parking brake: its switch is located in the dashboard, under the rotary light switch. Pressing this engages the electric parking brake, and pulling releases it. The brake 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.
Also included as standard equipment is 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 (HOLD function);
• 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 light. In emergency braking situations, it warns vehicles behind with flashing LED brake lights.
Overview of brake data:
Front axle Rear axle
Diameter Thickness Brake calliper Cast aluminium, ventilated, perforated
4-piston fixed calliper Cast aluminium, ventilated, perforated
1-piston floating calliper
Optional AMG Handling package for even greater driving dynamics
The new AMG Handling package available for the first time as an optional extra enhances the vehicle’s sportiness even further. In technical terms, it comprises an AMG Performance suspension with approximately 30 percent stiffer tuning, an AMG rear axle differential lock with setup tuned specifically to the vehicle, and also composite brake discs on the front axle. In the interior, the AMG Handling package differs from the standard appointments fitted to the
SLK 55 AMG with the addition of a three-spoke AMG Performance steering wheel finished in nappa leather with Alcantara® inserts in the grip areas.
Engine and power transmission
Fun with eight, economy with four
• High-tech: cylinder shut-off system inspired by Formula 1
• Efficient: fuel savings of 30 percent
• Exclusive: a combination of advanced technologies
• Powerful: 310 kW (422 hp) and 540 Nm
• Highly versatile: the AMG SPEEDSHIFT PLUS 7G-TRONIC
Superior power delivery, passionate response, high pulling power and a sonorous eight-cylinder engine sound – all combined with groundbreaking low levels of consumption: the naturally aspirated AMG 5.5-litre V8 engine in the new SLK 55 AMG provides pure excitement. The high-tech M152 powerpack enthralls with a combination of advanced technologies which is unequalled anywhere in the world.
No other petrol engine features direct injection at a pressure of 200 bar, spray-guided combustion and piezo injectors, in conjunction with map-controlled cylinder shut-off, an all-aluminium crankcase with “spectacle” honing, four-valve-per-cylinder design with continuous camshaft adjustment, a high compression ratio of 12.6:1, a ECO start/stop function and generator management – while revving to a maximum speed of over 7000 rpm. All these measures lead to high thermodynamic efficiency, which is a precondition for high efficiency and low exhaust emissions.
Moreover, deciding in favour of a large-displacement, naturally aspirated eight-cylinder unit with cylinder shut-off resolves the conflict of aims between high output/torque delivery and decidedly low fuel consumption levels. The reduction in fuel consumption of 30 percent compared with the previous model represents a quantum leap forward.
Key data at a glance:
AMG M152 5.5-litre V8 engine
Cylinder arrangement V8
Cylinder angle 90°
Valves per cylinder 4
Displacement 5461 cc
Bore x stroke 98.0 x 90.5 mm
Compression ratio 12.6:1
Cylinder spacing 106 mm
Output 310 kW (422 hp) at 6800 rpm
Output per litre 56.8 kW (77.2 hp)
Max. torque 540 Nm at 4500 rpm
Torque per litre 98.9 Nm
Maximum engine speed 7200 rpm
Engine weight (dry) 187 kg
Power/weight ratio 0.44 kg/hp
AMG Cylinder Management cylinder shut-off system
It is the AMG Cylinder Management cylinder shut-off system in particular – completely newly developed by Mercedes-AMG – that significantly improves efficiency: cylinders two, three, five and eight are shut off under partial load, which lowers fuel consumption considerably. In similar form this technology is also used in the approx. 750 hp V8 engines found in Formula 1. As efficiency also plays a major role at the pinnacle of motor racing, four or six cylinders are disabled by shutting off the fuel injection when the driver has lower load demands, e.g. when cornering at slow speed, in the Safety Car phases or for pit stops. In the case of the M152, the intake and outlet valves also remain closed. With a fuel consumption of 8.4 litres and CO2 emissions of 195 grams per kilometre (NEDC combined), the naturally-aspirated AMG V8 engine ranks at the same the level as its competitors, however these are unable to match either the output or torque of the SLK 55 AMG – and above all, they do not use large-displacement eight-cylinder engines.
The cylinder shut-off function is available over a wide engine speed range from 800 to 3600 rpm if the driver has selected transmission mode “C” – Controlled Efficiency. The AMG main menu in the instrument cluster informs the driver whether cylinder shut-off is active, and whether the engine is currently running in four or eight-cylinder mode. No less than 230 Nm of torque is still available in four-cylinder mode – enough power to ensure plenty of acceleration in most driving situations.
As soon as the driver has a need for more power and leaves the partial load range, cylinders two, three, five and eight are activated. The switch from four to eight-cylinder operation is immediate and imperceptible, leading to no loss of occupant comfort whatsoever. At an engine speed of 3600 rpm the activation process takes
no more than 30 milliseconds.
Valves closed, fuel delivery and ignition deactivated
This is made possible by intelligent interaction within the highly effective engine management system, with 16 hydraulically variable compensating elements and a complex oil supply system in the cylinder head. The variable compensating elements are integrated into the cylinder heads, and keep the intake and exhaust valves of cylinders two, three, five and eight closed. At the same time their fuel supply and ignition are deactivated.
This reduces the load-change losses of the four deactivated cylinders, and at the same time also increases the efficiency of the four remaining cylinders. This is because the operating point is transferred to the higher load range.
All-aluminium crankcase with Silitec cylinder liners
The crankcase of the naturally aspirated AMG 5.5-litre V8 engine features
a diecast all-aluminium construction. The low (dry) engine weight of just
187 kilograms is the result of uncompromising lightweight construction methods. The bearing covers for the main crankshaft bearings are made of grey cast iron and are bolted to the crankcase, from beneath as well as on the sides, for high rigidity.
The piston rings are carbon-coated to minimise internal friction and optimise wear characteristics. Cast-in Silitec cylinder liners ensure low friction for the eight pistons. So-called “spectacle” honing is another measure to reduce friction and therefore fuel consumption: in this sophisticated process, the cylinder liners receive their mechanical surface treatment when already bolted in place.
As honing would no longer be possible with the cylinder head installed, a jig resembling spectacles is bolted to the crankcase. The cylinder liners distort as if the cylinder head were in place, and are only then given their mechanical surface treatment. As a result, any static distorsion of the cylinder liners caused by tightening the cylinder head bolts can be completely eliminated. The positive effect of this process is reduced frictional losses.
Other measures to optimise efficiency include:
• weight-optimised cast aluminium pistons with special piston skirt coating
• optimised ventilation holes in the crankcase
• oil pump with electrically controlled pressure stage
• separate oil pump for cylinder shut-off as a controllable, low-friction vane cell pump
• engine cooling on the particularly efficient cross-flow principle
• electronically controlled fuel pressure, fully variable and demand-related between 100 and 200 bar
The forged crankshaft made of high-grade 38MnS6BY steel alloy rotates in five main bearings, has six counterweights and has been optimised with respect to torsional rigidity, inertia, low rotating masses and a long operating life. A two-mass viscous damper mounted at the front reliably eliminates vibrations. Each connecting rod journal on the crankshaft carries two forged, cracked connecting rods.
Four-valve technology with variable camshaft adjustment
Perfect charging of the combustion chambers is ensured by large intake and exhaust valves, of which there are two per cylinder. The exhaust valves, which are subject to high thermal loads, are sodium-cooled and for weight reasons also hollow. Four overhead camshafts operate the 32 valves via low-maintenance, low-friction cam followers. The infinitely variable camshaft adjustment within a range of 40 degrees on the intake and exhaust sides depends on the engine load and engine speed, leading to outstanding output and torque values.
This also results in consistent idling at a low speed. Depending on the engine speed, valve overlap can be varied for the best possible fuel/air supply to the combustion chambers and efficient removal of the exhaust gases. The variable camshaft adjustment is carried out hydraulically via four pivoting actuators. These are electromagnetically actuated and controlled by the engine control unit. The camshafts are driven by three high-performance silent chains, which have considerable advantages in noise comfort compared to cylinder roller chains.
ECO start/stop function as standard
The ECO start/stop function further contributes to the low fuel consumption. This system is standard equipment in the SLK 55 AMG, and permanently active in the fuel economy transmission mode Controlled Efficiency “C”. Once the driver comes to a halt e.g. at a red traffic light, the naturally aspirated V8 engine is automatically switched off. Once the brake pedal is released or the accelerator is depressed, the engine is immediately restarted and the car is able to move off quickly.
Intelligent technology guarantees a comfortable and immediate starting procedure: a crankshaft sensor which recognises the direction of rotation registers the resting position of all eight pistons. For an automatic engine start, the cylinder with the most favourable piston position receives an injection of fuel into its combustion chamber. The precise piezo-electric injectors greatly assist this process, as they make particularly fast starts possible. The M152 always starts in eight-cylinder operation.
The engine management ensures that the engine is only switched off if certain preconditions are met. The starter battery must have sufficient charge, for example, and the engine must be at the necessary operating temperature for efficient emissions control. The same applies to the interior temperature selected by the driver: if this has not yet been reached, the engine is not switched off when the car comes to a stop. The onboard network management system makes sure that active audio, telephone or video functions are not interrupted by the ECO start/stop function, and that the air conditioning continues to operate.
A framed “ECO” symbol in the AMG main menu shows the driver that the ECO start/stop function is active. When cylinder shut-off is active, the driver is informed by the symbol “ECO4”, while “ECO8” stands for eight-cylinder operation. Should one of the above criteria be preventing activation of the system, this is shown in the central display by the message “Start/stop inactive” and an “ECO” symbol with no frame. In the two more performance-oriented driving modes “S” (Sport) and “M” (Manual), the ECO start/stop and cylinder shut-off system are deactivated. If required, the driver can also switch the systems off while in “C” mode. In this case neither a “start/stop” nor an “ECO” symbol appears.
Generator management helps to save fuel
A generator management system makes a further contribution to fuel economy: whenever the naturally aspirated V8 engine is on the overrun or when braking, kinetic energy is used to charge the battery rather than being wasted as heat in the usual way.
In all other operating modes a combination of onboard network and generator management enables the generator to be kept at a low voltage. This reduces the load on the engine and makes for fuel savings of around 0.15 litre per 100 kilometres according to the NEDC standard, and up to 0.2 l/100 km in city traffic with its frequent overrun and braking phases. Highly efficient engine electronics for every function
All the engine functions are executed and controlled by a particularly efficient Bosch MED 17.7.3. control unit. This state-of-the-art engine computer not only controls the direct petrol injection, cylinder shut-off and variable oil supply, but also communicates with all the other onboard control units.
The microprocessor has more than 30,000 different parameters and functions stored in its memory, and is able to perform up to 260 million individual operations per second. To reduce the load on the engine control unit, the eight individual ignition coils have an integral electronic module known as an ignition amplifier at each cylinder. These ensure a strong ignition spark at all engine speeds and under all load conditions. Eight high-voltage powerstages are responsible for highly precise actuation of the piezo-electric injectors.
New AMG sports exhaust system with integrated exhaust flaps
For the first time AMG is using a sports exhaust system featuring an exhaust flap on each side. This technology resolves the conflict of aims between an emotional sound when driving in a sporty manner and a more discreet engine note in the partial load range. The main focus of the sound design was on achieving a perfect synthesis of perceptible dynamism and the long-distance comfort that is a hallmark of Mercedes.
Each of the two rear silencers has a flap which is variably activated on a logic-controlled basis depending on the driver’s power requirement and the engine speed. At low loads and engine speeds below 2000 rpm the flaps remain closed. This causes the exhaust gases to cover a longer distance and flow through an additional damping element, so that the engine sound is pleasantly subdued – resulting in a harmonious sound impression, especially in four-cylinder operation when cylinder shut-off is active.
When the driver accelerates, the flaps open at an angle of 15, then 30 and up to 50 degrees so that some of the exhaust gases cover the longer, acoustically dampened distance and some the shorter distance. This produces a sonorous engine note. Under full load at higher engine speeds, in performance-oriented eight-cylinder operation, both flaps are fully opened so that the occupants are able to enjoy the decidedly muscular sound typical of an AMG V8. In short, they are left in no doubt about the performance potential of the 310 kW (422 hp) naturally aspirated AMG eight-cylinder engine.
The two-pipe AMG sports exhaust system with two chromed twin tailpipes on each side has a pipe diameter of 65 millimetres from the manifolds to the pre-silencer. The diameter is reduced to 60 millimetres from the pre-silencer to the rear silencers.
Effective emissions technology with new catalytic converter boxes
Low exhaust emissions, compliance with country-specific standards and a characteristic engine sound – the requirements for the exhaust system of the new, naturally aspirated AMG 5.5-litre V8 engine were manifold and complex. The SLK 55 AMG complies with the current Euro-5 emission standard, as well as meeting all the requirements of the US market (LEV-III standard, On-Board Diagnosis II).
Air gap-insulated manifolds ensure a rapid catalytic converter response. For efficiency and to save space, this concept has a tandem catalytic converter housing on each side of the vehicle: adjacent to the firewall, two thin-walled ceramic substrates are grouped into each housing. This solution makes the previous, additional underbody catalytic converters unnecessary. The two ceramic substrates differ to ensure rapid and efficient emissions control: the front one is coated with palladium, while the rear one has a bimetal coating of palladium and rhodium. One lambda sensor per row of cylinders is located in front of each catalytic converter housing, and there is a lambda diagnostic sensor between each of the two thin-walled substrates.
Long tradition of powerful AMG V8 engines
As is typical of AMG, engine production is carried out by hand in the AMG engine shop. An engineer assembles the AMG 5.5-litre V8 engine according to the traditional “one man, one engine” philosophy, from installing the crankshaft through to adjusting the camshaft as well as fitting all of the wiring. An AMG engine badge bears the signature of the responsible engineer.
Powerful eight-cylinder engines are an inseparable part of AMG’s corporate history. Established in 1967, the company immediately caused a stir with the 300 SEL 6.8 AMG which succeeded in taking second place at the 24-hour race in Spa-Francorchamps (Belgium) in 1971. The AMG racing saloon was technically based on the Mercedes-Benz 300 SEL 6.3 with the M100 V8 engine.
With an engine output of 184 kW (250 hp) at 4000 rpm and a top speed of 220 km/h, this luxury V8 saloon with the M100 V8 engine was Germany’s fastest regular production car at the time. Classic tuning as well as an enlarged displacement from 6330 to 6835 cc resulted in an increase in output to 315 kW (428 hp) at 5500 rpm and in torque from 500 to 608 Nm.
Another important engine in the AMG story was the M117, its first eight-cylinder unit with four-valve technology. With a displacement of 5.6 litres, 265 kW (360 hp) and 510 newton metres of torque, this V8 accelerated the 300 CE 5.6 AMG to a top speed of 303 km/h in 1987. This made the coupé the fastest German car in series production, and American fans reverently christened it “The Hammer”.
The supercharged AMG 5.5-litre V8 of 2001 is another milestone in the history of AMG engine development: the M113 K delivered up to 428 kW (582 hp) and a torque of 800 newton metres. The supercharged AMG 5.5-litre V8 of the SLR McLaren dating from 2003 was even more powerful – the M155 generated up to 478 kW (650 hp) and 820 newton metres.
2005 saw the debut of the naturally aspirated, high-revving AMG 6.3-litre V8 engine known as the M156, which developed up to 386 kW (525 hp) and 630 newton metres. In the new C 63 AMG Coupé Black Series, this eight-cylinder engine delivered 380 kW (517 hp). From 2005 to the present day, more than 71,000 M156 engines have been produced – a record in the history of AMG. Exclusively reserved for the SLS AMG, the M159 likewise has a displacement of 6.3 litres and delivers a peak output of 420 kW (571 hp), with a maximum torque of 650 newton metres.
Closely related to the new M152, the AMG 5.5-litre V8 biturbo engine delivers between 386 kW (525 hp) and 420 kW (571 hp) depending on the model,
and a maximum torque of between 700 and 900 newton metres. The M157 is regarded as the most efficient engine in its output and displacement class.
The combined NEDC fuel consumption of the E 63 AMG is 9.8 litres per 100 kilometres.
The supercharged AMG 5.5-litre V8, the AMG 6.3-litre V8 and the AMG 6.0-litre V12 biturbo were all able to win the Best Performance Engine category several times in the International Engine of the Year Awards.
Highly versatile: the AMG SPEEDSHIFT PLUS 7G-TRONIC
The perfect partner to the naturally aspirated AMG 5.5-litre V8 engine used in the SLK 55 AMG comes in the form of the AMG SPEEDSHIFT PLUS 7G -TRONIC. This seven-speed automatic transmission has three transmission modes: Controlled Efficiency (C), Sport (S) and Manual (M), which can be selected by means of a button on the centre console.
In “C” mode, the Roadster generally moves off in second gear and makes use of the high torque already available at low engine speeds to shift up to the highest viable gear as quickly as possible. The resulting dethrottling effect on the intake side lowers fuel consumption. In modes “S” and “M”, the engine and transmission take on a much more agile character, with higher engine speeds, more spontaneous gear changes and faster shift times. The automatic double-declutching function which is now active when downshifting as well as the brief, precisely defined interruption of ignition and injection when shifting up under full load shorten shifting times and increase emotional appeal when adopting a sporty driving style. The seven gears can be changed via the AMG shift paddles on the steering wheel. The upshift indicator integrated into the AMG instrument cluster informs the driver when a manual gearchange is advisable.
A double turbine torsional damper integrated into the transmission and fitted with centrifugal pendulum which adapts to engine speed helps to minimise vibrations in four-cylinder mode and enhances the impression of comfort experienced by the vehicle occupants.
The Mercedes-AMG management comments on the new SLK 55 AMG “Inspired by Formula 1: top performer for fuel economy and maximum output”
“A top performer for fuel economy and maximum output: with the new SLK 55 AMG we have created a real masterpiece. The naturally aspirated AMG V8 engine sets an outstanding example for efficiency, while at the same demonstrating the creativity and expertise of our engineers, who took their inspiration from Formula 1 when developing the cylinder shut-off system.”
Ola Källenius, Chairman of Mercedes-AMG GmbH
“A sports car engine with technology taken from Formula 1 – I am convinced that the new SLK 55 AMG will meet the high expectations of all sports car fans. Talented driving dynamics are firmly embedded in its genes, and as such the eight-cylinder roadster provides exhilarating driving pleasure.”
Tobias Moers, Head of Overall Vehicle Development and Board Member of Mercedes-AMG GmbH
“Thanks to the innovative AMG Cylinder Management system and other high-tech components, our newly developed AMG 5.5-litre V8 engine achieves the fuel economy of a four-cylinder engine with the muscular power delivery and emotional sound experience of a V8.”
Friedrich Eichler, Head of Engine & Powertrain Development
“As the only eight-cylinder roadster in its segment, the SLK 55 AMG is a unique vehicle. As a result it is the perfect embodiment of the AMG brand claim of ‘Driving Performance’.”
Mario Spitzner, Head of Branding and Marketing