Mercedes-Benz SLK55 AMG: New engine details

Mercedes-Benz is not prepared to officially confirm it just yet. But normally reliable sources at its AMG performance car division suggest the all-new SLK, the R172 as Mercedes-Benz insiders call the upcoming two seater, will receive a new V8 engine in top-of-the-line SLK55 AMG form. 
The naturally aspirated 5.5-litre unit is essentially the same powerplant used in the S63, CL63 and CLS63 sans turbochargers and associated plumbing.
Power is said to be raised by 62bhp on the 5.4-litre V8 used in the outgoing SLK55 AMG at 422bhp. That’s 82bhp more than the twin-turbocharged 3.0-litre six-cylinder engine in the BMW Z4sDrive35iS and turbocharged 2.5-litre five-cylinder in the Audi TT RS - both of which kick out 340bhp.
Combined with the latest incarnation of Mercedes-Benz’s seven-speed 7G-Tronic automatic gearbox featuring a reworked torque converter for faster shifts and reduced power losses, it should easily eclipse the 4.9second 0-62mph time of the existing model launched in 2004.
The new SLK55 AMG is planned to make its world debut at next year’s Frankfurt auto show, six months after standard versions are due to bow to the public.

Pictures and video of the 2012 model year Mercedes-Benz SLK can be seen here:
http://theautoinsider.blogspot.com/2010/12/all-new-2012-model-year-merc-slk-leaks.html