383/496 6 pack Build

I think the best thing you could do, is buy a decent pair of bare aluminum heads and go as far with them as your budget will support. Then call Tim, at Bullet and have him spec you a camshaft. Go with a 3/8" pushrod diameter from Manton, Smith Bros or another reputable manufacturer. I'm not a fan of gear drives, I know some people like them. I think the harmonics transferred can do more harm, than the supposed gains from not incurring chain stretch. If I were building something more along the lines of a max effort deal, I'd go with a Jesel belt drive. For what you're doing, I'd buy a good, three bolt double roller chain.