Quote Originally Posted by RonnSulli View Post
Instead of using aluminum heads what if I was to go with a set of GT40's?
Not a worthwhile investment,give this a good read:Five.Oh Info : The Ultimate Ford GT40 and GT40P Cylinder Head FAQ also both the aluminum heads and the 289 heads have an adjustable valve train,the GT's do not as you can see the HP gains would be minimal too, in fact possibly less than the stock heads because the 289 heads have more compression.More education here: http://www.mre-books.com/interchange/interchange5.html Now that being said since the early 289 heads are almost the same as the the 289 Hi-Po's there is a budget trick that has been done to improve flow when you get that valve job done you can use these:1 84" Intake Valves SB Chevy 305 V8 SBC Small Block Stock Steel Set of 8 | eBay You do not want to go larger because it would involve more machine work you can do some port matching and minor porting to the exhaust as the exhaust is a weak link with stock heads,this is where the aluminum heads really pack some of their punch,but bottom line the Flo-Teks are the real bargain.Like most of us down the road we think this is fun but "more is better" those heads can be swapped on to a 351W