damn zip, i forgot i got pro comp heads on our nova. bought them from my machinist when he found a crack in my heads. i was using a old set of chevy fuelly heads from a vette.yea it was a vette engine,. im the one who took it out of the car.lol anyway these heads i gave 200. for and they were ready to go. aluminum heads ready to go for 200. yea ill try them. been 3 yrs and i run them hard. real hard. but no nos.damn i forgot all about them heads.