Inline fours. Inline sixes. V-8s. V-10s. V-12s. No matter what you're into, BMW has a great soundtrack for you.
The M1 Procar was a racing version of BMW's 1970s M1 supercar, powered by a 470-horsepower M88/1 inline-six that could rev to 9000 RPM and built for a one-make racing series. The series folded soon after it was founded, but thankfully the cars live on.