Zip,The heads Ihave are edelbrock cnc from chapman.If I remember right they flow around 350,I'm not sure because I got them used and damage.I have heard of some comp guys getting in the 400 range but there stuff is way above me.370 from brodix sounds real good.My 412 is race gas 750 proform,lots of tunning to get it to leave good at 2000 rpm foot braking.Last years cam was crane 260/268 .712/.644 at the valve with racing springs and lash set.New cam is Bullet 267/275 .708/652 4 7 swap check the same way.Bill.