The AMG SPEEDSHIFT MCT 7-speed sports transmission is a newly developed power transfer unit that is used exclusively in the new Mercedes-Benz SL 63 AMG.

Combining the best of both worlds: the sporty, direct and agile responsiveness of a manual transmission, yet still maintaining maximum comfort of an automatic transmission.

Equipped with seven gears, four driving modes, a double-declutch function and a RACE START function, the MCT 7-speed sports transmission tops any previously unattained flexibility.

MCT stands for Multi-Clutch Technology, and indicates that gearchanges are executed solely by the clutch components.

The main attraction of AMG SPEEDSHIFT MCT 7-speed sports transmission is it's wet start-off clutch, which operates in a sump and replaces the previous torque converter. Thanks to its low rotational inertia, this transmission is extremely responsive, with movements of the accelerator immediately translated into motive power.

Equipped with four driving modes, the transmission shifts the gears with no interruption in tractive power, providing some what tailor-made shifting for maximum driving pleasure.

In "C" mode the gearchanges are comfort-oriented, with "soft" accelerator mapping for smooth cruising.

In "S" mode the engine and transmission respond more immediately, with more revs in each gear and faster downshifts.

Changing to driving mode "S+" shortens shift times by up to 60 percent, while "M" provides the most sporty mode of all. In "M"mode the 6.3-litre AMG V8-engine responds more sharply, while gearchanges take only 100 milliseconds.

Particularly fast and responsive multiple downshifts are another major attribute of the AMG MCT sports transmission. Kickdown allows the driver to change from seventh directly to fourth gear, for example, or from fifth to second gear which all equals to fun on the racetrack.

The central control unit for the AMG SPEEDSHIFT MCT 7-speed sports transmission and all the dynamic functions is the AMG DRIVE UNIT. The electronic rotary switch for selection of the driving modes, including activation of the innovative RACE START function, is located to the left of the shift lever.

Below this there are three keys for other functions: the first controls the ESP system, the second the ABC suspension and the third, which bears AMG lettering, enables the driver to store the selected driving mode and the suspension setup.

Briefly depressing the AMG key displays the configuration options, and longer pressure saves the preferred setups to memory.

Being the most powerful roadster in its class, powered by the 6.3-litre AMG V8-engine developing 386 kW and 630 newton metres, the SL 63 AMG accelerates from 0 to 100 km/h in 4.6 seconds and has an (electronically limited) top speed of 250 km/h.