Can anyone tell me what intake and exhaust valve sizes were installed in the following casting numbers.
casting # 3931063 oval port closed chamber date code D11-9
casting # 3964290 oval port closed chamber date code H20-9
These heads are virgin rebuildable as removed from running engines. Is there any differences between these heads other than casting number and dates? Purchase of these heads depends on your knowledge of these heads. I have not visually looked at them so I need good info. Thanks