"In 1992, Audi left the German DTM racing series after a controversy around the crankshaft design of their V8-powered race cars. After using the road car's cross-plane 90°-crankshaft for several years, they switched to a flat-plane 180° version which they claimed was made by "twisting" a stock part. The scrutineers decided that this would stretch the rules too far."
Look up the Cosworth DFV. 3.0L V8 400hp @ 9,000 RPM's then the DFY version in 1983 had over 500hp @ 11k RPM's.
http://en.wikipedia.org/wiki/Cosworth_DFV