So, I pick up the heads from the machine shop after they replaced valve seals, installed with JWT spring/shim kit, and resurfaced/cleaned them up. I didn't notice this until I went to drop them off at the mechanic doing my rebuild (he pointed it out to me):



You can see the one line made by whatever machine/cutting tool is a bit deeper, and you can actually feel it/catch your fingernail running across it one direction like a tiny stair step. I don't know how to measure that, but am taking it back to the machine shop to have both sides resurfaced again (to keep compression equal on both sides).

At this point, I'm starting to worry about valve-piston clearance issues cropping up if too much is cut off the bottom of the heads. JWT says there's no valve-piston clearance issues with the C8 cams and OEM pistons, but I don't know how much clearance there is to work with when resurfacing heads. Going to call them tomorrow and ask, then go tell the guy to re-redeck the heads. What you experts out there think?

Anyone know OEM deck height?

 

Shop resurfaced the head, it wasn't very deep, and apparently a shaving of aluminum caught and dragged across the head cutting it like that. Odd.