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