From next year onwards the BMW M6 range is going to offer three variants for the first time, with the regular M6 Coupe and M6 Convertible models to be joined by a brand new M6 Gran Coupe based on the luxurious 6-Series Gran Coupe that has just gone on sale.

Spotted here testing on the Nürburgring and on some of the German race track’s surrounding roads, the upcoming M6 Gran Coupe looks to have received the same visual modifications as its two-door cousins, right down to the aggressive front spoiler and extra-wide rear tires.

Click here to watch the spy video in full via our YouTube page.

The car will target the Mercedes-Benz CLS63 AMG as well as an upcoming Audi RS7, which like the BMW is still in development.

Power should come from the same M-tuned 4.4-liter turbo V-8 found in various M models including the M6 Coupe and M6 Convertible. However, output may be lifted beyond the current 560-horsepower limit to somewhere around 600 horsepower. Drive will be sent to the rear wheels via BMW’s M-DCT seven-speed dual clutch transmission.

Look out for the M6 Gran Coupe to make its official world debut later this year before landing in showrooms early next as a 2013 model.