Originally Posted by pbonsalb
I would say at least 99.9%. There are only several built motor supercharged M3s that I have read of. Few people will spend another $10k to build a motor on top of the supercharger kit\ and you get only about 10% more power for spending twice as much money.
I had to comment this, but that's def off; no one I have seen w/ a built motor is running over 15-20psi and on a built LC motor that will make a very big increase.
I would def do a 9-10:1 over a built 12:1 all day long. Nicer to be able to run higher boost