In the 80s I messed around with drag race cars. We ran crankcase pressure evacuation systems to the headers. The tubes went into the header collector at an angle and we had a one way check valve to prevent pressure from going into the engine.

Tower sells a small check valve http://www3.towerhobbies.com/cgi-bin...?&I=LXG850&P=7 and they should be fairly easy to find at auto parts stores.

Carrell