I'm putting parts together for my 42' coupe engine. the heads I have are off a 72' truck I'm not building anything special my question is instead putting money into those should I consider a set of gt40 heads instead? Any fitment issues I should consider? What manifolds should I also be looking for? Thanks Sent from my SAMSUNG-SM-G891A using The H.A.M.B. mobile app
The GT40 heads would be an upgrade but they take special exhaust manifolding! If you can,get the exhaust with the heads!! ROY.
If those 72 heads take much work, you're better off saving up and getting aftermarket aluminum heads. Or, if you're like me, you like to spend hours grinding down thermactor humps and opening up the exhaust runners because you don't really have a life, go for it.
Thanks I'll make sure to grab the manifolds when I grab the heads Sent from my SAMSUNG-SM-G891A using The H.A.M.B. mobile app
You'll need new pushrods with the GT40 heads too. The ones off the roller cam donor motor won't work, they'll be too short with a flat tappet cam. The 'P' heads will give a bit more compression, but also have valve rotators on the exhaust and valve springs that won't cut the mustard with a hi-po cam, so these aren't a 'simple' bolt-on. Both heads are worth about 25-30 HP give-or-take at the top of the tach, less down lower.
The GT40 heads also have the rotators, but they can be eliminated with a set of offset valve retainers (specifically for eliminating rotators) from Ford Racing (plus I recommend the matching valve springs from Ford) that will result in equal spring heights.
I'm running the p heads on my engine. you just need plug wires with 90 degree boots and headers. manifolds wont work. They run fine. I have changed the valve springs away from the rotators. My car made 299 ft lbs to the wheels with these heads on a stock short block.
If you're not building anything special, just plonk a set of late model E7' heads on it. They have herdened seats for modern gas and are "cheap as chips"
Don't waste the money on e7 heads. Might as well keep the old heads. Gt40 and P heads are great. Or find early 70's 351w heads. I think pre '73. CN
The early heads aren't suited for Unleaded Gas, and the cost of hardened seats is more than a pair of E7's He could sell the early heads. Ford explorer heads are a better choice [GT40P's] at a cost We can all be internet heroes when it comes to spending other peoples money The OP did say "He wasn't building anything special"
Early 69-70,351W heads have huge combustion chambers and will need domed pistons to get you back to a decent compression!Later 351W heads are the same as 302-5 Liter heads! ROY.
This is a good read about Ford heads: http://www.fiveohinfo.com/performance/gt40-gt40p.html With the costs of machine work these days a better "bang for the buck" might be here: http://www.speedwaymotors.com/Flo-Tek-203505-Small-Block-Ford-Aluminum-Cylinder-Head,46332.html