PCV issue

toolmanmike said
I re-read this thread and I see you have a 318 with a solid lifter cam and of course adjustable rockers. Valve lash does some goofy things with these engines. I have used different specs for my 273 and it runs best when I adjust them on the loose side of spec. The motor is pretty noisy when I start it cold and quiets down a bit at operating temp but here is still a bit of clatter even when warm. It seems to like it that way. It is crisper and revs easier. tmm

Adjusting the lash looser is kinda like putting in a slightly smaller cam. More lash means less lift and duration. Old racer's trick to tune their engines for a particular track is to vary the lash. Maybe your particular engine, being a small one, would like a smaller cam. Or it's possible that if you tighten the lash and tune the rest of the engine for it it'd run better yet.