Pcv bov

vacuum 6

Well-Known Member
To help with blow-by I've come up with a PCV BOV. Instead of running a evac to the breathers its run to the PCV. In vacuum it works just like a normal PCV system however in boost the check valve cracks at .3 psi then fully opens at 4 psi (pump turns on).

Looking at the picture the bottom port in placed into intake. The upper port goes to vacuum with a rubber hose between it and the PCV. The barb goes to the pump.


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Sounds interesting. Not to hijack your thread I had a similiar idea a month ago when there were some threads on those catch cans. I pretty much used two of those 3/8" kynar check valves from US Plastics. They crack at half a pound. Put both of them after a T just past the moisture seperator I bought from eastwood.

Here is a diagram of what I did.

Here are the pics.

Before installation engine would suck oil via PCV after install nothing!


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