Yes, heads are stock volume. No detonation at all. I asked the machinist if it would be wise to the shave the heads when rebuilding. He warned not to do this for the reason you mentioned. So, we didn't.
Disclaimer: I am not an auto mechanic. I may not have the timing set correctly. My timing light says I do but, its a cheapy I bought at Sears. If I missed the mark, its a good miss!
