"The BMW M1 Procar is a race car that was used between 1979 and 1980 in the BMW M1 Procar Championship.

The Procar Championship was created due to motorsport rules and regulations changing drastically during the M1's production time, preventing it from entering most motorsport events."

More info on BMW M1's in motorsport: http://en.wikipedia.org/wiki/BMW_M1_Procar_Championship