I have a 69 Camaro with a 396. I built it pretty much stock. It has a solid cam, open chamber heads, Edelbrock Performer RPM, 800 Holley, Hooker headers. The bottom end is balanced, steel crank, recon. rods, line bored, with stock replacement forged domed pistons, the 325-350 hp replacement. I have a set of 290 castings, which are closed chamber. I am having them redone, with one size bigger valves-2.19"/1.88". They are way ported. The guy I bought them from had about 80 hours port work time. I am wanting to run these on my engine along with a Comp 306 solid Magnum cam. The lift is .629"/.629" both on intake and exh. I was wondering with this combo, if I would have enough piston to valve clearance. The rep at Comp Cams helpline said I probably would, but I would hate to buy a new camshaft and install it, and find out I don't have the piston to valve clearance, and then be stuck with the cam, because it had already been installed. Also, if my budget allows, I would maybe like to run the 308 Comp Solid roller with .652"/.652", but there again who knows on piston to valve clearance. I was wondering if there were anyone out there that has this sort of combo, and how much piston to valve clearance do they have? Any info would greatly be appreciated.