Thanks for your response. Yes, there will most likely be some milling. We're planning on tearing the heads down in a few weeks and having them magna-fluxed and milled as needed. I need to understand compression ratio better. Could you please share your calculations for the equation you provided below. I researched and found several threads on Google stating the #64 heads on a 400 was a great idea, just doesn't happen often as they are hard to find. I know the #64 heads were built better with larger valves and screwed in studs. They will also allow the Dougs Headers I'm planning on installing to bolt right on. The guy helping me rebuild the heads is a Pontiac (exclusive builder) and stated this was the way to go.
Here's two of the articles. They will bolt right on and I should be over 300HP using pump gas...
