crank case ventilation

[Bugzilla]

Originally posted by BergRace
You need a header with the vacuum pipe in the middle of the collector, along with a one high-flow one-way valve at the conection hose.

Yup. It's called an eductor, and I run one on my baja: http://rap.midco.net/bugzilla/new_wheels/wheels022.htm
http://rap.midco.net/bugcollector/DSCF033.jpg
http://rap.midco.net/bugcollector/apr03001.jpg

It is very simple to build one... just weld a piece of pipe to the exhaust, near the collector. Get a one-way valve (I think it is a GM part) and thread it on the pipe. Then run a hose from the valve to the breather tower, or any place on the case you want to vent. I tapped the valve covers and connected them to an aftermarket breather with an oiled foam element. This provides a place for clean fresh air to enter the crankcase. The eductor pulls quite a bit of vacuum, and you don't contaminate your intake charge... it all goes out the exhaust. The one-way valve keeps any pressure pulses (like a backfire!) from traveling to the crankcase.

If you want more details on how I built mine, let me know.

Troy