Thanx for the advice guys...i guess ial have to look for other heads.. i really want vortecs heads up in ontario canada there hard to find.all the ones i've found will only be sold with the motor and on ebay and shipping would kill me from the states..i do have a set of rebuilt 305 heads laying around but i was told to stay away from them....they have small cc but i herd they dont breethe well and they will only go to 5000 RPM has anyone used them...