As for re-using them 30 Mile Lifters I would . But it really is Best to always run New on New so the Camshaft will break in right . The Camshafts Listed are Hyd Flat Tappet Grinds . You would want Good Hi-Rev Hyd Lifters . You can Pull your Camshaft out and mark the lifters in/ex per Cylinder and sell it on this Forum . Now I am thinking Your Double Hump Heads are 1.94"in/1.50"ex Heads and you do need screw in studs and Better Valve springs up to 500" Lift installed . And if you run the EX268H Camshaft I would say with out Looking at a P.C Engine Dyno you will have a Real H.P of 380-385 at around 5500-5600 RPM's . If your Double Hump Heads need all the work as above . Look into buying different Heads . If you do not want to do the intake/valvecovers and rocker arm change out . Look at these Heads they Flow just a bit Less on the Intake Side and a bit more on the Exhaust then the #906 GM Votecs that need screw instuds Stronger Springs and the Valve seal Bosses to be Cut Down to work on this Build .
http://www.competitionproducts.com/p...?number=4266KA Price for Pair . Yes these heads out flow you D/H Heads so you should have a 357-400 H.P Build with them . But Like Rumrumm Said the AFR's are the Top Dog I don't think they could be beat on the Top of this Build . But they sure will set you back with there Co$t .