Hello all. I am Installing an offenhauser valve cover to a 250 Chevy. I have read, and have been told, that this valve cover will leak oil because there is no pvc provision. I realise the engine must be able to breath but was wondering what others have done to correct this problem. Not wanting to cut-up, grind, or install baffles into this aluminium cover. I have seen the offenhauser bolt on breather caps, and aftermarket pvc/oil cap but not sure if this combination will be sufficient to allow the engine to breath. Also what is the best gaskets members have used on the V/C and side plates.

Main problem I had was the cover is badly warped on the gasket surface.
Had to use a couple gaskets glued together.Plus I had machined the bottom gasket surface as much as I could w/out getting too thin,& it still was not straight.

I prefer the rubber gaskets over cork.


MBHD

I had the same issues as MBHD in that the gasket surface was not flat side to side or end to end. For that matter, neither was the head gasket surfaces. I ended up using a silicone gasket making material to fill the wider mismatches.

I'm not sure on the newer style engines but the valve cover gasket I got for my GMC from Best Gasket was the thickest and freshest one I have ever seen. Right Stuff from Permatex will seal it but it wont be fun to get back off. Maybe use it to stick the gasket to the cover. I like the bolt on breathers but have found them to be another source of leaks. Beater