I did a 470" low deck.4.375 x 3.900, 6.760 rod. Right at 10.2:1. 84cc Eddys and a small dish(mirrors the chamber) w/.039 felpro's at 0 deck.I know I could have went higher,but I am unsure what pump swill will be available in a couple yrs. Has a 242/248@.050 solid roller,runs great on 93 and no ping on 89(that was an oops at the gas station ) This is a street only car.Hope that helps.