[bubba428]

hmmmmm what piston are you running in that? did you check the V-P clearance??? I can't quite grasp why this is happening. I'm running a .525/.546 lift cam on a set of #416 heads off a 305 I found in the junk yard that has 2.02/1.60 put in and .550 lift clearance. I've revved this to 6k without a peep from the valvetrain. did you replace your rocker nuts or give 'em the ol' sledge whack? I noticed that with the intake I put on my build that on one side the intake bolt goes too far into the head and actually hits the push rod, it mangled the hell outta my push rod. maybe you have a similar compatibility issue????