I bought a 383 crate engine and the whole engine had to be dissassembled due to the fact that the people who put the engine together knew JACK poopie. Anyways, I put my alum. L98 heads on it after they were ported out. So, I have a set of heads here and they have a GM production number stamped into them. Problem is that I don't know what heads these are. They are said to be stage 2 ported, 3 angle valve job heads with this number stamped into them
Any ideas as to what heads these are? I think my mechanic said they looked like vortec heads.
Casting # on my original '89 heads is 10088113. I believe the current production I installed had the same number, but it's a different design (the intake manifold bolts are counterbored for a gasket retainer and the rocker studs no longer include the factory guideplates). I recall someone posting info about casting #'s. You might want to try a search under Heads.