SLS AMG gets its wings

The revival of the SL Gullwing has turned from rumour to reality, with Mercedes-Benz revealing even more details on the upcoming SLS AMG supercoupe.

Merc used the Geneva Show as an on-paper debut, and new details of the Mclaren SLR replacement have come to hand over the weekend. Noticeably smaller than the SLR, the SLS sits on a featherlight aluminium spaceframe shaving about 135kg of the former's porky 1620kg, and amounting to a power-to-weight ratio of 2.84 kg/hp.

The AMG 6.2L V8 develops 420kW at 6800 rpm, and 650 Nm at 4750 rpm sent through the rear wheels. It sprints from 0 to 100 km/h in 3.8 seconds and topping out at 315 km/h (though Merc say all figures are provisional). And that's through a seven-speed sequential - finally, the five-speed auto can be rightfully retired.

The SLS is scheduled for release this time next year (in Europe).

Just last month, Mercedes said the power wars were over. They lied...

OFFICIAL PRESS RELEASE
The Return of a Sports and Racing Car Legend: The New 'Gullwing' from Mercedes-Benz - the SLS AMG
March 13 2009
Stuttgart - For the first time in the company's history stretching back over 40 years, the Mercedes-Benz performance brand of AMG is presenting a vehicle developed entirely in-house, the Mercedes-Benz SLS AMG. This super sports car serves up an exciting proposition with its unique technology package: aluminium spaceframe body with gullwing doors, AMG 6.3-litre V8 front-mid engine developing 420 kW peak output and dry sump lubrication, seven-speed dual-clutch transmission in a transaxle configuration and sports suspension with aluminium double wishbones. The ideal front/rear weight distribution of 48 to 52 percent and the vehicle's low centre of gravity are testimony to the uncompromising sports car concept.

"Mercedes-Benz is presenting an exhilarating super sports car in the guise of the new SLS AMG, which is bound to set the pulses of all car enthusiasts racing that extra bit faster. The SLS AMG is emotion pure and simple for the Mercedes-Benz brand and is set to become one of the most alluring sports cars of our era", says Dr. Dieter Zetsche, Chairman of the Board of Management of Daimler AG and Head of Mercedes-Benz Cars.

"Our customers will experience with the SLS AMG the expertise of our sports car manufacturer Mercedes-AMG, built up over 40 years of motor racing, along with the kind of scintillating design that only a top athlete from the Mercedes-Benz stable can offer", says Volker Mornhinweg, Chairman of Mercedes-AMG GmbH.

The new Mercedes-Benz SLS AMG offers purist, distinctive styling, superior driving dynamics and hallmark Mercedes everyday practicality and safety.

During the development of the new 'Gullwing', the AMG developers placed their trust in the valuable know-how of the specialists from the Mercedes Technology Centre (MTC) in Sindelfingen. The aim of this joint development was to turn the SLS AMG 'Gullwing' into the perfect synthesis of the strengths of the Mercedes-Benz and AMG brands.

Consistent lightweight design thanks to aluminium

The radical design as a highly talented dynamic super sports car with its low-slung front-mid engine set well back also feeds through into the proportions as well as the optimised lightweight body concept: for the first time, Mercedes-Benz and AMG are presenting a car with an aluminium chassis and body.

Compared with the traditional steel design, this results in a significant weight saving, clearly illustrated in the planned DIN kerb weight of 1620 kilograms excluding driver.

The newly developed bodyshell comprises an aluminium spaceframe. This exclusive design combines intelligent lightweight design with outstanding strength - thus delivering superlative driving dynamics.

Naturally, the aluminium spaceframe meets all the requirements in terms of passive safety and the hallmark Mercedes-Benz body quality that applies to any car sporting the Mercedes-Benz star.

Despite the low sitting position in typical sports car fashion, the wide-opening gullwing doors make it easy to get in and out of the vehicle.

Fine-tuned AMG 6.3-litre V8 engine developing 420 kW

The fine-tuned AMG 6.3-litre V8 engine achieves a peak output of 420 kW at 6800 rpm, thus turning the SLS AMG into one of the most powerful sports cars in its segment.

A power-to-weight ratio of 2.84 kg/hp comes courtesy of the low vehicle weight.

The eight-cylinder naturally aspirated engine delivers maximum torque of 650 Nm at 4750 rpm.

The 'Gullwing' accelerates from 0 to 100 km/h in 3.8 seconds, before going on to a top speed of 315 km/h (all figures are provisional).

Bearing the internal designation M159, the V8 high-revving engine with its displacement of 6208 cubic centimetres has been thoroughly reengineered compared with the M156 entry-level engine and boasts all the hallmarks of powerful racing engines.

The principal measures in increasing output include the all-new intake system, the reworked valve train and camshafts, the use of flow-optimised tubular steel headers and the dethrottling of the exhaust system.

This results in much better cylinder charging, which feeds through into an increase in output to 420 kW with maximum torque of 650 Nm.

The eight-cylinder engine responds swiftly to movements of the accelerator pedal, demonstrating much more pronounced high-revving flexibility across the entire rev range.

The switch to dry sump lubrication also translates into a much lower position of the engine in the vehicle. And lowering the vehicle's centre of gravity has also paved the way for high lateral acceleration and exhilarating driving dynamics.

Perfect synthesis of lightweight design and strength

The use of high-strength components compensates for the increased engine load associated with the higher output.

Forged pistons, a reinforced crankshaft bearing, optimised crankcase structure, along with improved lubrication thanks to an on-demand high-performance oil pump ensure optimum durability.

Despite these higher loads, the engine weight for the M159 has been further reduced.

The forged pistons as oscillating masses play a particularly valuable role in this respect.

Thanks to targeted weight optimisation, the weight of the engine has been reduced further, resulting in a kerb weight of 206 kilograms and, in turn, a power-to-weight ratio of 0.36 kg/hp.

The AMG 6.3-litre V8 engine thus delivers the best figure by far compared with its competitors.

Sophisticated catalytic converter technology enables current and future exhaust emission standards such as EU 5, LEV 2 and ULEV to be met.

The friction-optimised twin-wire-arc-sprayed (TWAS) coating on the cylinder walls - a process that remains exclusive to AMG- also reduces fuel consumption, as does the on-demand, map-optimised oil supply along with the regulated generator management.

Thanks to the targeted use of efficiency-enhancing measures, fuel consumption for the SLS AMG is around 13 litres of Super Plus per 100 kilometres (NEDC combined, provisional figure).

Dual-clutch transmission with transaxle configuration and torque tube

The AMG 6.3-litre V8 engine delivers its abundant power via an ultra-light carbon-fibre driveshaft at the rear axle - similar to the set-up used on the DTM C-Class racing touring car.

The transmission is mounted at the rear (transaxle principle) and is connected to the engine housing via a torque tube.

A carbon-fibre shaft rotates at engine speed in the torque tube. The advantages of this sophisticated solution are associated with the rigid link between the engine and transmission and, in turn, the optimum support for the forces and torque generated.

A new AMG dual-clutch transmission with seven gears takes care of power transfer.

The transmission boasts fast gear changes with no loss of tractive force.

The driver has a choice of four different driving modes, ranging from comfortable to extremely sporty, as well as a RACESTART function.

Optimum traction comes courtesy of the mechanical differential lock, which is integrated in the compact transmission casing.

The chosen solution with a front-mid engine plus transaxle configuration ensures an ideal front/rear weight distribution of 48 to 52 percent.

Mounting the engine behind the front axle has created the ideal conditions for consummate driving dynamics with precise steering, first-class agility, low inertia with spontaneous directional changes and outstanding traction.

The suspension technology is also a match for these high standards: wheel location comes courtesy of double wishbones and hub carriers made of lightweight forged aluminium.

The 'Gullwing' comes with 3-stage ESP® as standard, providing the driver with access to the three "ESP ON", "ESP SPORT" and "ESP OFF" modes at the push of a button.

Ceramic composite brakes, innovative flow-forming wheels

The AMG high-performance composite brakes all-round ensure extremely short stopping distances even under enormous loads.

The newly developed, optional ceramic composite brakes with larger brake discs guarantee even better brake performance and lower unsprung masses. The ceramic brake discs will perform reliably at even higher operating temperatures thanks to their greater hardness, all combined with an impressive weight reduction of around 40 percent.

Light-weight design was also a key consideration with the wheels: weight-optimised AMG light-alloy wheels - 9.5 x 19 inch (front) and 11.0 x 20 inch (rear) - based on the innovative flow-forming principle reduce the unsprung masses while increasing driving dynamics and suspension comfort.

265/35 R 19 (front) and 295/30 R 20 (rear) tyres developed exclusively for AMG ensure optimum grip.

The design and development phase for the super sports car got underway in the last quarter of 2006. The intensive vehicle testing programme will be complete by the end of 2009. Meanwhile, the reinterpretation of the legendary 'Gullwing' is scheduled to be launched in the European Spring of 2010.