The new Mercedes SL 55 AMG

Details of the new SL 55 AMG have been announced and the exceptional high-performance roadster from Mercedes-AMG has made further substantial advances in terms of technology, design and appointments. Reengineered AMG sports suspension based on second-generation Active Body Control is the key, and more direct steering and new AMG high-performance brakes bestow the two-seater with prodigious handling abilities. Meticulous attention to detail is also a feature of the new-look body and interior, with highlights including new AMG steering-wheel shift paddles and an AMG main menu with a RACETIMER. The improved AMG 5.5-litre V8 supercharged engine now has a new supercharger compressor and more efficient engine management unit to boost power from 368 kW (500 hp) to 380 kW (517 hp), while the peak torque has been increased from 700 to 720 Nm. The engine management can now set the optimum combustion point individually for each cylinder, resulting in a further improvement in the efficiency of the AMG V8 engine. The new SL 55 AMG accelerates from 0 to 100 km/h in 4.5 seconds (outgoing model: 4.7 seconds) and goes on to reach an electronically limited top speed of 250 km/h, though motorists with an extra-dynamic streak can opt for the AMG Performance Package which ups the limited maximum speed to 300 km/h.

AMG SPEEDSHIFT 5-speed automatic transmission with AMG shift paddles

As in many of the high-performance models from AMG, the AMG SPEEDSHIFT five-speed automatic transmission is responsible for transmitting the engine's power to the wheels of the SL 55 AMG. Drivers are able to choose between fully automated gearshifts or changing gear manually: manual gear-changes can be performed either by using the selector lever or by pulling on the silver-coloured aluminium AMG shift paddles marked "up" and "down" for that true Formula 1 feel.

In the manual drive mode "M", the driver is able to capitalise on the tremendous pulling power of the V8 supercharged engine as the transmission will not shift down automatically, even at full throttle; the selected gear will be retained even with the accelerator in the kickdown position. In manual mode, AMG SPEEDSHIFT will not automatically shift up a gear either when the rev limit is reached, enabling sportily-minded drivers to harness the immense power reserves even more effectively. The transmission will shift down a gear when the engine speed approaches the lower limit of the rev band. The technical credentials of AMG SPEEDSHIFT also include torque converter lock-up from first gear, active engine-braking downshifts plus an "optimum gear" function, which combine with spontaneous, lightning-quick gearshifts to produce a truly thrilling motoring experience. An optimised torque converter has also been added as part of the facelift package. Not only has the new torque converter been adapted to handle the increased torque of the V8 supercharged engine but its smaller diameter produces a lower inertia; this in turn sharpens the engine's responsiveness, particularly when travelling at slow speeds.

AMG sports suspension based on Active Body Control for extra agility

The AMG sports suspension based on second-generation Active Body Control has been specially reengineered for the AMG Roadster. The specific measures that have been implemented reduce body movements in dynamic driving situations to levels even lower than those achieved by the outgoing model, without impairing the excellent ride comfort in any way. The SL 55 AMG now offers an even sportier drive, especially in extremely dynamic situations such as those encountered on the race track. Another special feature of Active Body Control is the variable roll moment distribution between the front and rear axles, which the system adjusts automatically to suit the vehicle's current speed. The modified control produces even greater agility than before, particularly when travelling at typical country road speeds.

The superior agility and handling precision can also be attributed to the revised elastokinematics at the front axle as well as to the modified speed-sensitive power steering. A steering ratio that is now seven per cent more direct gives the SL 55 AMG even greater manoeuvrability. The modified valve control logic for the power assistance translates into faster response when the steering is centred. The AMG engineers have also fitted a new power steering pump with a higher rate of delivery that guarantees an optimum degree of power assistance no matter how quickly the steering wheel is turned. Finally, the inclusion of a new steering damper makes for peerless driving comfort.

Newly developed AMG high-performance composite brakes

The SL 55 AMG is equipped with newly developed AMG high-performance brakes which ensure optimum metering of braking power, extremely short stopping distances and even better resistance to fading. Large, internally ventilated and perforated composite brake discs with six-piston aluminium fixed callipers are fitted at the front wheels, while the rear wheels are slowed down by internally ventilated and perforated discs with four-piston fixed callipers.

...continued