What do the bearings look like?. I had the same "look" on a few of my pistons when my engine detonated. It also showed up on the main caps and block mating surface. Really shows up in the bearings.
Spun a couple of rod bearings, metal through the engine, lost cam lobes etc. Mains looked OK all things considered.
JMO here but you lost the cam lobes first.. metal
got into the bearings and the piston was just damaged
in the aftermath... a cam doesnt lose the lobes in a
moment it will take a bit of time.. again.. JMO
