I have a set of 452 heads that I took off a 470" engine we raced. They have 3/8" stem 2.08" /1.74" valves in them. The heads have had a serious amount of porting done and we moved the short side radius way over (offset rockers and epoxy), roof raised .350". This engine ran 5.60's in a 2100# foot brake door car in the 1/8 mile, turning the engine 7,000 rpms. No idea what they flow as it never mattered to us. When we built a 526" engine we used the same cam we had in the 470" engine, but used...
Real World Flow Differences 2.08"/ 1.74" Valves vs 2.14"/ 1.81" Valves " Pictures Added"
