Thanks a million guys. But I have a question(I'll show my ignorance on this one) but,this cam supposedly lets a motor 'flaten out' around 5500 rpm,and so would these heads I think. 500caddy,I know to use a little more converter than the cam needs, but 4500-5000 stall? I'm not questioning your experience,and I don't know alot but are you baseing that on the rpm potential due to it being a small cubic in.motor or??? Please explain.