SL 63 AMG Comes with 7-Speed Sports Transmission and without Torque Converter

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SL 63 AMG Comes with 7-Speed Sports Transmission and without Torque Converter


2008-02-11 – The new Mercedes-Benz SL 63 AMG is powered by an AMG 6.3-l V8 engine developing 386 kW and 630 Nm and comes with an AMG Speedshift MCT 7-speed sports transmission – MCT stands for Multi Clutch Technology and only employs clutch elements to perform gearshifts. The new power transfer concept features a compact, wet start-up clutch that replaces the conventional torque converter. Result is a direct connection to the powertrain, together with double-declutching and Race Start functions. The new SL 65 AMG will also be launched alongside the SL 63 AMG. The V12 6.0-l biturbo develops 450 kW and 1000 Nm of torque.

The transmission is an all-new concept which combines the sporty, direct and agile feedback of a manual transmission and the convenience of an automatic transmission. It is fitted with seven speeds, four drive modes, a double-declutching and Race Start function. The transmission is designed for high torque and maximum revolutions up to 7200 rpm. It also comes with sufficient reserves even under high loads thanks to its oil cooling system. An electronic transmission control unit fully controls and monitors all processes. A new two-stage torsion damper effectively eliminates vibrations. The MCT 7-speed sports transmission has been developed jointly by Mercedes-AMG and Daimler, although it will be used in AMG vehicles. It is produced at the Mercedes-Benz Esslingen-Hedelfingen production facility.

At the heart of the MCT 7-speed sports transmission lies the wet start-up clutch, which runs in an oil bath and replaces the previous torque converter. Thanks to its low rotational inertia, the transmission responds instantaneously and dynamically with no slip. Accelerator pedal movements trigger an instant traction response. Fitted with four drive modes: “C” (Comfort), “S” (Sport), “S+” (Sport plus) and “M” (Manual), the transmission provides gearshifting with no loss of tractive force and supports customised control strategies for driving pleasure. In “C” mode the gearshifts are comfortable, coupled with a “soft” accelerator response set-up for outstandingly smooth power transfer. In “S” mode the engine and transmission interact with more “bite”: the engine speed is allowed to reach a higher level in each gear; the downshifts also feel more spontaneous. The gearshifts are around 20 percent faster than in “C” mode. Switching to “S+” mode cuts another 20 percent off shift times, while “M” is the sportiest mode: here the 6.3-l V8 engine has even more bite, added to which the transmission shifts gear another 10 percent faster – a reduction of 50 percent compared with “C” mode. In “M” mode the gearshifts take just 100 milliseconds.

The 6.3-l V8 engine teams up with the MCT 7-speed sports transmission to form for dynamic driving. The car accelerates from 0 to 100 km/h in 4.6 sec before, top speed is at 250 km/h (electronically limited). The high-revving naturally aspirated engine generates 386 kW at 6800 rpm from a displacement of 6208 cc, delivering maximum torque of 630 Nm at 5200 rpm. The combination of high-revving concept and large displacement achieves high pulling power at low engine speeds coupled with high-revving flexibility – right up to 7200 rpm.