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Auto news; Mercedes-Benz Snags “Best of Whats New” Award For Transmission Popular Science awards Mercedes AMG SPEEDSHIFT MCT 7-speed sports transmission with “Best of What’s New” award. In testing for the award, Popular Science gave the transmission as fitted in the 2009 Mercedes-Benz SL 63 AMG Roadster first place in the “Automotive” category. A total of 100 products were in the running for the ..Auto news;

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Popular Science awards Mercedes AMG SPEEDSHIFT MCT 7-speed sports transmission with “Best of What’s New” award. In testing for the award, Popular Science gave the transmission as fitted in the 2009 Mercedes-Benz SL 63 AMG Roadster first place in the “Automotive” category. A total of 100 products were in the running for the final selection.

Employed exclusively in the SL 63 AMG Roadster, the AMG SPEEDSHIFT MCT 7-speed sports transmission claims to combine the sporting, direct nature of a manual transmission with the convenience of an automatic. Like Audi/VW’s DSG transmission, this AMG transmission uses wet-plate clutches as opposed to a torque-robbing torque converter to allow the SL 63 to break static friction from launch. Unlike the Audi/VW unit, Mercedes’ unit employes just one row of gears. Once underway, gearchanges are managed with alacrity and computer-controlled finesse, and rev-matched downshifts don’t disturb the chassis even in extreme driving and cornering.

The transmission offers four modes: C, S, S+, and M. In C (comfort), gearchanges are optimized for smoothness and a luxurious experience. S (sport) mode offers quicker responses, faster downshifts, and pushes the 6.3-liter AMG V-8 to higher rpm in each gear. S+ shortens shift times even further (20 percent quicker than S mode), and finally the M mode yields shifts that occur in just 100 milliseconds.

Last but definitely not least is the Race Start function on the new transmission. Race Start deftly balances maximum traction with maximum acceleration, taking these duties out of the hands of the driver and handing them off to vehicle microprocessors. The end result? 0-62 mph in a fleet 4.6 seconds.–Colin Mathews