Quote Originally Posted by tomtom123 View Post
Superchargers are like 35% parasitic on an engine whereas a turbo is like 0% parasitic. I read that on these forums somewhere back a few years ago.
Because of the extra energy the engine has to use to turn the supercharger through the belts and everything, it is parasitic. A turbo, which is spun by the exhaust gasses, is not parasitic. Thats why at the same boost level, a turbo will help produce more power
Not trying to nitpick you, you are mostly right, just want to point out that there are some parasitic losses with using a turbo. The turbo behaves like an exhaust restriction to some degree, which necessitates the engine working somewhat harder. Can't say exactly how much harder. Still worlds more efficient than the M90, though.