I picked up my 76 455 yesterday and decided to remove the heads and intake since they are worthless to me. upon removing the heads i found that there was no ridge at all on the tops of the bores. upon inspecting the pistons i noticed a slight difference betwen a couple of them. same size dish and all but some had rings on top and two didnt..i decided this was going to require further disassembly for inspection.. when i got it apart i found 6 of the rods had been beamed and 2 werent. obviously somebody has been into this engine at some point in the past. i'm wondering if it's stock bore or oversized. I cant find any oversize stamping on the pistons and they look like stock low compression pistons to me.. can anybody here shed some light on this for me? picture below is one of the pistons i removed
the look like stock gm pistons , someone might have been in there for something. i would inspect everything and mic your pistons/bores could you see the rings when piston was in engine? you could put pistons in and use feeler guages to see how much piston clearance .
