[goodyear1984]

gt40 heads are like a e7 with a band-aid.yea they flow a little better,have bigger valves.they dont flow enough on a 302 so dont bother with putting them on a 351.there are so many advantages of aluminum heads..if you sit and think about it u will spend 1300 for a set of good aluminum heads that are brand new...say u get a set of gt40 heads for 200.then to rebuild then springs 150,valve job 150,mill 100,seals 40,hot tank 50.there is around 700 bucks might be less or more depending on what needs to be done to them and the prices at your machine shop.now you have 700 into a set of production iron heads that flow a little better that stock and are good for a 302 nothing bigger.lets say in 2 years you decide you want to build a 331 or a 347 stroker if you have aluminum heads you can run more compresion on pump gas,they weigh half what a iron head does, they flow way better ,make more power.if you donthave the money now i would stick with the e7 and port them.i got 5 tenths inthe 1/4 mile when i ported a set.then when you have the money buy the aluminum.ive seen people make this mistake befor and are not happy that they barley notice a differance when they bolt on a set on gt40's.its a better bang for your buck to buy the right heads now and not have to buy a different set inthe future