[Cliff R]

.078" quench is HORRIBLE in one of these engines, even worse using factory iron heads with their flat chamber floors/machined combustion chambers.

Good thing you have a RAIV cam in it, or it would pound the rod bearings out of it in a week due to detonation. The RAIV cam saves the day here as it bleeds off a LOT of cylinder pressure and pushed peak VE high in the RPM range. Put a 10 degree smaller cam @ .050" in this build on a 110LSA and it wouldn't last a month......IMHO....

+2 on moving the heads away from the pistons to increase valve to piston clearance. These engines have a BUTT-LOAD of that right to start with with factory "low lift" cams in them.

The only Pontiac engine I ever had close for piston to valve clearance was a 455 with forged TRW Super Duty pistons in it (2 small valve reliefs). With a 276/284 @ .050" cam with .750" lift it still had just under .040" piston to valve bumping it thru without a head gasket in place. The heads were CNC ported early round port E-heads at 330cfm with 72 cc chambers (milled to .068cc).

So basically, without writing a book here on building these engines and checking critical areas during the process, piston to valve with the cam you are using shouldn't even be on the list of things to worry about........FWIW........