N63B44

We may get to see turbocharged M cars from BMW soon, if an unnamed source cited by Automotive News is right. The next generation 2011 BMW M5 based on the new F10 car set to debut in 2010 may get its cylinders cut by 2 and replaced by two turbochargers, much like the 4.4 litre twin-turbocharged V8 found in the BMW X6 xDrive50i.

The current production version of the N63B44 produces 408hp between 5,500 to 6,400rpm and an M5-beating 600Nm of torque between 1,800 and 4,500rpm, but the insider reported that a variation of the N63B44 twin-turbocharged V8 under testing in BMW’s engineering labs producing over 536hp and even more ridiculous amounts of torque. They will still need to squeeze more out of the engine if they want to beat Audi in the horsepower game. Audi currently leads in the premium D-segment performance car race with its recently unveiled Audi RS6, sporting 580 horsepower and 650Nm of torque.

BMW may end up leaving the high revving 8,400rpm madness of normally aspirated engines only in the BMW M3 in the next generation of M cars, with the upcoming lightweight M-ish 1-Series getting a turbocharged motor as well, but for weight reasons.

But if this really happens, the M DCT has to be strengthened first to take on the far higher level of torque that turbocharged engines typically put out.