What I do know is that I have friends who's cars that had cylinder heads from a 360 and 2.02 intake valve's ran better when they went with 1.880" intake valve's. And you don't neccesarily have to spin a engine higher rpm's with a cam and cylinder head change unless the cam is pretty radical. Most guys I know their cars run great and don't spin them over 5500 -6000 rpm's