Here's an excerpt from The SC installation manual:
(61) Now we need to setup the crankcase breather system. You have two options available depending on your use of the car and the engine condition. We found that under hard acceleration with the engine hot, dense oil vapors (blow-by) can contaminate the intake air, which in excess could cause detonation (with or without a supercharger). Some cars have more blow-by than others.
Option #1: Leave the original valve cover breathers in place, which run together to the air filter housing.
Option #2: Use a push in valve cover breather(s) vented to a catch can. This requires putting a hole, slightly less than 1.25”, in the valve cover. If you do extended track events (road racing) or your engine has an excessive amount of blow-by (worn rings), you should install this breather in the forward upper corner of the drivers side valve cover (determine the proper location by looking at the valve cover from the inside). It’s not necessary for regular street use. A good oil separator / breather to use is the Moroso part # 68781, which is available at speed shops for about $7.
Additionally, if doing track events, we suggest the following:
- Use race gas.
- Put a tie wrap on the dipstick handle to hold it down.
- Consider installing a second valve cover breather.
We used to put those Moroso breathers in the installation kits, but found nobody was using them. I've had one on my car for several years now and have no oil, at all, in the tube running to the air filter housing. We're working on a screw in breather also, for those that don't want to put a hole in their valve cover.
Regards,
Sean