Following on from the recent launch of the SL 63 AMG, the top eight-cylinder model, there now comes the presentation of the new Mercedes-Benz SL 65 AMG, the V12 roadster in the line-up from the Stuttgart-based manufacturer. The AMG 6.0-litre V12 “biturbo” (twin-turbocharged) engine develops a maximum output of 463 kW (630 hp) and maximum torque of 1000 Nm (738 lb-ft). The result: exceptional performance, impressive power delivery and effortlessly superior dynamics. As with the SLS AMG super sports car, the use of an all-aluminium bodyshell results in a drastic reduction in weight. The new SL 65 AMG is some 170 kilograms (375 lbs) lighter than before. The expressive front section is dominated by the new “twin blade” radiator grille and the front apron’s lower cross strut in high-sheen chrome.
“The combination of exclusive V12 dynamic performance and a refined roadster driving experience was already the defining attribute of the predecessor model. We are convinced that, with the new SL 65 AMG, we have developed an incomparably exciting high-performance vehicle for the small, but loyal community of fans”, says Ola Källenius, CEO of Mercedes-AMG GmbH.
An important aspect of the new model is the intelligent lightweight construction which also contributes to reducing the fuel consumption. At 11.6 litres per 100 kilometres (NEDC combined) it represents a saving of 2.4 litres or 17 percent compared with the previous SL 65 AMG and simultaneously establishes a new benchmark in the twelve-cylinder petrol engine segment. A major role in the reduced fuel consumption figures is played by the AMG SPEEDSHIFT PLUS 7G-TRONIC transmission, the ECO start/stop‑function, in-engine measures to optimise efficiency and alternator management. Despite the significantly reduced fuel consumption, the maximum output of the AMG V12 6-litre biturbo engine is up from 450 kW (612 hp) to 463 kW (630 hp). The maximum torque is 1000 Nm (738 lb-ft).
The unrivalled performance figures of the new SL 65 AMG translate into an exceptional driving experience: acceleration from 0 to 100 km/h (62 mph) takes 4 seconds with the 200 km/h (124 mph) mark attained after just 11.8 seconds. The top speed is 250 km/h/ 155 mph (electronically limited). As well as offering stunning acceleration, the AMG twelve-cylinder biturbo engine impresses with its smooth running characteristics and its distinctive AMG V12 sound. It is a performance that reconciles effortless superiority and stylishness to perfection.
The AMG 6-litre V12 biturbo engine with the designation M 279 is based on the M 275 engine used previously and has been comprehensively revised for the new SL 65 AMG. New exhaust gas turbochargers with an increased spiral cross-section, new manifolds and wastegate ducts with optimised flow characteristics increase the engine output by 13 kW (18 hp). The multi-spark ignition with twelve double ignition coils not only results in smoother running, but also enables even more effective combustion in combination with a new engine management system with higher performance and optimised cylinder heads. The resulting reduction in exhaust emissions is also due to a large extent to the optimised catalytic converter system. The newly developed AMG sports exhaust system, which has a pipe layout with enhanced flow characteristics, is 3.2 kilograms lighter as a result of a reduction in the wall thickness.
But it is not just the inner qualities of the AMG 6-litre V12 biturbo engine that impress. The powerplant’s looks are as inspiring as its performance: the high-quality carbon-fibre and aluminium engine cover reflects the exceptional character of the powerful twelve-cylinder unit.
For the first time AMG has combined the 6-litre V12 biturbo engine with the AMG SPEEDSHIFT PLUS 7G‑TRONIC. The seven-speed automatic transmission with its wide gear ratio spread enables a significantly lower engine speed and helps to reduce fuel consumption. A new fuel economy torque converter, bearings designed for reduced friction loss and the transmission-oil thermal management system are responsible for a further increase in the efficiency of the power transmission system.
The AMG SPEEDSHIFT PLUS 7G‑TRONIC has four different driving modes – Controlled Efficiency (C), Sport (S), Sport plus (S+) and Manual (M) – which can be selected at the push of a button on the centre console. In “C” mode the ECO start/stop function is permanently active. The compelling, dynamic character of the driving experience is made all the more vivid by the automatic double-declutching function during downshifts and through the brief, precisely defined interruption of ignition and fuel injection during upshifts under full load; the latter functionality has the additional benefit of reducing the shift times.
Compared with the predecessor model’s steel design, the all-aluminium bodyshell of the new SL 65 AMG delivers a significant weight saving of around 110 kilograms as well as superior rigidity, safety and comfort. Intelligent lightweight construction also means that the components have been optimised in line with their specific purpose. Various types of processing are used for the aluminium components, for instance, which are produced as permanent mould castings or vacuum die castings before being processed into extruded sections or used in the form of sheet aluminium with varying wall thicknesses. The result is high rigidity, high safety and improved vibration characteristics. For the cover behind the tank, the designers use even lighter magnesium material in certain areas. High-strength steel tubes are integrated into the A-pillars for safety reasons.
The boot lid helps to further trim the weight. For the first time on a volume-produced model, the inner support is made from lightweight carbon-fibre composite. The extremely rigid carbon-fibre component is bonded to the plastic outer shell, resulting in a weight saving of five kilograms compared with a conventional boot lid – an innovative solution that is being pioneered with the AMG SL models. This raft of innovative lightweight-design measures means that, at an EC kerb weight of 1950 kilograms (4299 lbs), the new SL 65 AMG is 170 kilograms (375 lbs) lighter than the model it replaces.
Mercedes-AMG also makes systematic use of lightweight construction principles for the suspension. The steering knuckles and spring links of the 4-link front suspension and almost all of the multi-link independent rear suspension components are made of aluminium. Both the vehicle’s handling agility and the response of the spring and damper components are enhanced by the reduction in unsprung masses. Like the predecessor model, the new SL 65 AMG is equipped as standard with the ABC active suspension system. The AMG sports suspension based on Active Body Control fitted in the eight-cylinder SL 63 AMG has been enhanced and its setup optimised for this new top-of-the-range model.
Driving dynamics and performance were the key objectives during the design, development and testing phases. It is possible to choose between two suspension settings at the touch of a button: distinctly sporty characteristics with reduced roll angles and firm body damping (“Sport”) or a mode for high comfort on long journeys (“Comfort”). More negative camber on both axles and fully revised elastokinematics result in greater agility and faster cornering speeds.