With the new 6-Series Gran Coupe being a rival for Mercedes CLS, it is only natural for BMW to make an M version of the car , and take on the CLS63 AMG with it.

They are indeed doing so, as the first prototypes of an M6 Gran Coupe have already been spotted out in the wild. Although it’s like two years away from its market launch, but already the big CLS is getting worried.

The M6 Gran Coupe will be getting BMW’s new 4.4 liter bi-turbo V8 with 552bhp and 501lb ft of torque. The CLS63 has a 5.5 liter bi-turbo V8 but it makes 518bhp and 516lb ft. Both cars hit 60mph from nought in about 4.5 seconds, and both have a limited top speed of 155mph.

But the fact is the M6 Gran Coupe is basically a sportier version of the M5, and that’s, to all intents and purposes, the best sports saloon in the world. It will look very good too, what with the M paraphernalia added to the Gran Coupe’s natural beauty. Granted, the CLS63 will sound better than this, because AMG’s always do, but that wouldn’t be enough to drive the customers away, would it.

The M6 GranCoupe will be unveiled closer to 2013. It must wait for the two-door M6, which will be revealed later this year, to get its feet grounded.

via: Autocar