Intake valve, there was lots more on the exhaust. It is an auto
I would not try to slice hairs with piston to valve clearance with a 383. I've bent several intake valves and actually busted a head with these issues and a 383 with flat tops. hydraulic cams make matters worse. what ever the tappet pre-load is is how much the tappet will pump up and how much valve lift will increase if the springs are floated. i'll almost bet you have .515" lift at the valve with adjustable rockers; could be wrong but doubt it. i'd almost bet you've got some retainer to guide issues if your using unmodified iron heads. tight lobe separation angles and advancing the cam will decrease piston to valve clearance on the intake side.
We are using solid lifters so the valve lift should be consistent. Looking back on it, we should have invested in a set of pistons so this would not be an issue but the ones we have are new from when this build was started many years ago... so we will work with what we have for now and build a proper motor after the car is on the road.
I hear ya. Last winter, we (my father and I) rebuilt a 440 that had evidence of this too. And it even had valve reliefs in the pistons. This is why dad wants to use the thicker head gasket for added insurance but then we drop in compression by almost half a point. It’s a perfect 9.5:1 with the steal shim gasket. Would we really be loosing that much performance dropping to 9:1?
Yes, the heads are ported 906 and rebuilt with heavier springs. The lash will be set at .020”. We were unsure about running the hydraulic cam with solid lifters, but Jim from racer brown said it’s not an issue. We always push toward a solid lifter set up when building an engine, especially a Mopar.
