What are the 452 aluminum heads? Are they the ones being offered by Pro Max? Does anyone have any experience with them? I run factory 452's on my road runner. They're race ported with oversized valves. We did them over 10 years ago for a N/SS motor. I think we had close to $1500 into these heads with machining, new valves and springs, and the port work. Hind sight being 20/20 we should have opted for the Eddy's (They weren't available at that time). If for no other reason...40 pounds off the nose helps a ton. Tom