Advanced AMG 6.3-litre V8 engine with an output of 571 hp
The heart of the new SLS is a high-powered eight-cylinder engine manufactured by Mercedes-AMG. The advanced 6.3-litre V-8 engine, which has an output of 571 hp at 6,800 rpm, makes the gullwing vehicle one of the most powerful sports cars in its segment. In conjunction with the low vehicle weight, this results in a weight-power ratio of 2.84 kg/hp. The naturally aspirated engine provides its maximum torque of 650 Nm at 4,750 rpm. The gullwing vehicle accelerates from 0 to 62 mph in 3.8 seconds and has an electronically limited top speed of 197 mph (all figures are preliminary). The high-torque V8 engine, which is called the M159 within the company, has a displacement of 6,208 cc. It has been completely restructured compared to the basic M156 engine, and it displays the typical characteristics of high-performance racing engines.
The most important measures taken to boost its performance were the development of a completely new intake manifold system, the restructuring of the valve gear and the camshaft, the use of streamlined steel-pipe fan-type exhaust pipes and a dethrottling of the exhaust system. As a result, the designers have achieved significantly improved cylinder charging that boosts performance by almost nine per cent. The eight-cylinder engine reacts nimbly to movements of the accelerator pedal and in general responds extremely well. Thanks to the change to dry sump lubrication, it has been possible to achieve a much lower installation position for the engine. The consequent lowering of the vehicle's centre of gravity enables high transverse acceleration, which results in handling dynamics that drivers love.
The perfect synthesis of lightweight construction and stability
The use of high-strength components compensates for the increased burden on the engine resulting from its higher output. Forged pistons, a strengthened crankshaft mounting, an optimized crankcase structure, and improved lubrication by means of a need-regulated high-powered oil pump ensure maximum stability. In spite of the increased demands placed on it, the engine weight of the M159 has been further reduced. The forged pistons, as oscillating masses, make a particularly valuable contribution to this reduction. This results in a dry weight of 205 kg, and thus a weight-power ratio of 0.36 kg/hp -- a value that is unmatched by any competitors. Sophisticated catalytic converter technology makes it possible to comply with current and future emissions limits such as EU5, LEV2 and ULEV.
Reaching ambitious fuel consumption targets
In spite of its uncompromisingly sporty character, the vehicle has reached ambitious fuel consumption targets. The SLS AMG returns 21.4 mpg (combined; preliminary figure), which makes it the front runner in its competitive field. It boasts efficiency-boosting measures such as the AMG-exclusive, friction-optimised LDS cylinder-bore lining, an oil supply that is regulated according to the characteristic map, and smart generator management. During every coasting phase of the vehicle and every braking action, kinetic energy is used to charge the battery rather than being uselessly transformed into heat, as happens in conventional engines. Conversely, the generator is switched on without a load during acceleration and thus eases the burden on the engine.