More details have emerged of Mercedes-Benz's SL65 AMG Black Series, the most extreme and powerful SL powered by a twin turbo V12 and due to go on sale in Europe this November.Just 350 of these carbonfibre-bodied supercars will be built by AMG, using standard SLs as the donor car. The engine, a tweaked version of AMG's V12 with new turbochargers, will put out 670bhp and 737lb ft; 66bhp more than a standard SL65. That means a 0-60mph time of 3.8sec and a top speed of 199mph.The car will use the five-speed automatic transmission with AMG's Speedshift electronics. Mercedes' seven-speed gearbox is not strong enough to take the engine's torque.The body, all made from carbonfibre except for the rear wings and the doors, contributes an overall weight saving of 266kg which means the SL Black Series will weigh 1850kg in total. Other weight saving measures include replacing the folding metal roof with fixed roof, also made of carbonfibre, and stripping out the interior. The seats are made from carbonfibre, along with the dashboard and door cards which helps to give the SL65 Black Series 53:47 weight distribution. The bespoke body has another function to cover the exceptionally wide axles, which have the front and rear tracks increased to 1639mm and 1666mm.The car itself is 4589mm long, 1960mm wide and 1286mm tall; that's 57mm longer, 133mm wider and 12mm lower than a standard SL. These axles, along with other technologies developed for this car, will be used in the forthcoming Mercedes-badged, AMG-engineered upercar called SLC that will indirectly replace the SLR in 2009.