ok so i picked up a 302 from a buddie block was done .030 over needs to be built. but n e ways i would like to freshen up my stock gt heads new valves, valve springand i am doing roller rockers. i would like to mayybe get the heads ported n polished. but after buy the 306 i dont have to much to play with, i am looking for a nice power gainnothing crazy and the best bang for my buc. i have no clue what valve springs, valves, and port n polish. any input u guys have will help alot. i have maybe 300-400 to spend on the heads thanks again (i know this may be a lil cheap to do all new or after market parts or just may coast that much for the shop work)