Just about every Mercedes-Benz model now has a corresponding AMG derivative (AMG is Mercedes' performance division) and the just-released SL 500 sports car is already available as the high-performance SL 55 AMG. With a new, supercharged version of Mercedes' 5.5 litre V8 engine developing 476 horsepower, and a 5 speed automatic transmission with optional manual shift capability, the SL 55 AMG will do 0 to 100 km/h in just 4.7 seconds, and reach a speed of 200 km/h in about 15 seconds.
Visually, the SL 55 AMG can be distinguished from the SL 500 by its unique bumpers, distinctive side skirts, 18-inch multi-spoke wheels and four chromed tailpipes. Inside, there is aluminium trim with a sand-cast effect, AMG sports seats for extra lateral support, and cockpit instruments with silver-coloured symbol dials and red needles. The seats are trimmed in leather and feature an AMG pattern. Interior safety features include a new type of head/thorax bag in the doors, two-stage airbags for driver and passenger, newly developed integral seats, and the automatic, sensor-controlled 'pop-up' roll-over bars. The SL 55 AMG's power-operated convertible hardtop goes up or down in just 16 seconds.
The SL 55 AMG's special 5.5 litre V8 features a newly developed belt-driven supercharger between the cylinder banks. It works on the principle of a "Lysholm" compressor and achieves about 30 percent more charge pressure than other comparable belt-driven supercharging systems. In addition, a separate oil cooler is installed in the front bumper.
AMG engineers modified nearly all the mechanical components in the original SL 500 V8 engine, including the crankcase, crankshaft, pistons, oil sump, cylinder head, camshafts, valvetrain, and ECU. The displacement of the AMG engine is now 5439 cc, 473 cc more than the engine in the SL 500.
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For the first time in a Mercedes-Benz passenger car, a Formula-1-style gearshift with two selector switches located behind the top two steering wheel spokes is offered. To use it, the driver must first activate the manual mode by pressing a program select button on the automatic selector lever. The selector switch on the right of the steering wheel is used for upshifts whilst the one on the left is for downshifts. The transmission will change up on its own if the maximum permitted engine speed is reached. If the SL 55 AMG comes to a stop without the driver shifting down manually, first gear is selected automatically. A display on the instrument cluster tells the driver which transmission mode is active and which gear is selected.
Like the SL 500, the SL 55 AMG includes new 'drive-by-wire' Sensotronic Brake Control (SBC). A microcomputer oversees the operation of the brakes - a vacuum-powered brake booster is no longer required. Among the characteristics of Sensotronic Brake Control are the extremely fast build-up of pressure and the precise monitoring of driver and vehicle behaviour by a sophisticated sensory system. Emergency braking is a good example: if the driver switches quickly from accelerator to brake pedal, SBC recognises the early signs of an emergency situation and reacts automatically. With the help of the high-pressure reservoir, the system raises the pressure in the brake connectors and instantaneously presses the pads onto the brake discs, which can then be applied with full force the moment the brake pedal is pressed. Taking emergency braking at a speed of 120 km/h as an example, this "priming" of the braking system reduces the stopping distance by some three percent.
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Sensotronic Brake Control works in tandem with the Electronic Stability Program (ESP) which keeps the car on track by applying precise brake impulses at individual wheels and/or by reducing the engine torque. SBC also offers higher levels of safety than a conventional system when braking through corners. Whilst conventional braking systems apply the same brake pressure ratio to the outer and inner wheels when cornering, SBC allows the brake force to be distributed according to the situation. Consequently, the system automatically increases the brake pressure on the outer wheels when cornering, as they produce more brake force by virtue of their greater contact forces. At the same time, the brake force on the inner wheels is reduced. The result is more stable braking and optimum stopping distances.
Sensotronic Brake Control offers further benefits on wet roads. In wet weather, the system injects regular, short brake impulses to ensure that the film of water on the brake discs is wiped off and SBC can work as effectively as possible at all times. This automatic dry braking function is activated in intervals whenever the car's windscreen wipers have been running for a certain time.
Active Body Control - a Mercedes-Benz development - is also fitted as standard on the new SL 55 AMG. The system adapts the suspension setting automatically to the driving situation. The most prominent components in the active suspension system are hydraulically controlled servo cylinders, which are located together with passive shock absorbers and coil springs in the suspension struts, where they work together as a suspension control system: the actively controlled elements reduce body vibrations of up to five hertz occurring, for example, on uneven road surfaces as a result of body lift and roll, when cornering, if the car leans heavily to the side, or through the typical pitching of the car body when braking. Compared with steel suspension systems, Active Body Control can greatly reduce vibrations of this kind.
AMG engineers added special ABC suspension struts with sporty, stiffer damper settings for more spontaneous steering characteristics. They also reset the algorithms for the active suspension and other control systems (ESP(r), Brake Assist, DISTRONIC). Further special features of the AMG chassis include: a rear axle with reinforced wheel location components, steel sub-frame and spring links, made using an extremely robust welded steel construction; brakes with internally ventilated and perforated brake discs (diameter 360 or 330 mm) on both axles. The front pad face is almost twice as large as it is in the SL 500: 220 square centimetres in all; 18-inch wheels with new multi-spoke design (8.5 J x 18 at the front and 9.5 J x 18 at the rear); low-profile tires, 255/40R-18 at the front and 285/35R-18 at the rear.
SL 55 AMG standard equipment
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Active Body Control (ABC)
Aero windscreen wipers
Adaptive front airbags
Adaptive accelerator
Active Service System ASSYST
AMG sports seats
Anti-lock Braking System (ABS)
"Audio 30" car radio
18-inch wide-profile tyres
Brake Assist system
Anti-theft alarm system
Electronic Stability Program (ESP(r))
Headlamp Assist
Power windows
Five-speed automatic transmission with touchshift, manual transmission mode and steering wheel gearshift
Belt tensioners and belt force limiters
Air-conditioned glove compartment
Head/thorax bags in the doors
Remote-release boot lid
Interior lighting with night design
Integral seats, electrically adjustable
Automatic climate control
Leather upholstery
Light-alloy wheels (18-inch) with AMG multi-spoke design
Electrically adjustable steering column
Memory function for seats, steering wheel and mirrors
Multicontour backrests
Multifunction steering wheel with AMG styling
Rain sensor
Headlamp wash/wipe system
Sensotronic Brake Control (SBC)
Seat heating
Cruise control with SPEEDTRONIC
TIREFIT with electric air pump
Sensor-controlled roll-over bar
vario-roof
Draught-stop
Xenon headlamps
Central displays in instrument cluster
Central locking with remote control and crash sensor
Anodised aluminium trim
Optional equipment includes:
DISTRONIC autonomous intelligent cruise control
Active seat ventilation
Car phone
Bixenon headlamps
CD changer
COMAND
PARKTRONIC parking aid
Interior motion sensor
KEYLESS-GO
Panoramic vario-roof (from mid-2002)
TELEAID emergency call system
Automatic tyre pressure monitor
Sound system
LINGUATRONIC voice-operated control system
TELEDIAGNOSIS and MB-Info (telematics services)
TV receiver (in conjunction with COMAND)
Technical data: 2003 Mercedes-Benz SL 55 AMG
Engine
5439 cc V8, 3 valves per cylinder
Horsepower
476 at 6100 rpm
Torque
700 NM at 2650-4500 rpm
Compression ratio
9.0 :1
Transmission
5-speed automatic with manual transmission mode and steering wheel shift
Chassis
Front axle
Four-link suspension, Active Body Control
Rear axle
Multi-link independent suspension, Active Body Control
Brakes
Sensotronic Brake Control electro-hydraulic braking system -, 4 disc brakes, internally ventilated and perforated at front, internally ventilated and perforated at rear, ABS, Brake Assist, ESP(r), pedal-operated parking brake
