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Why not have a Fox?
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Discussion Starter · #1 ·
So as you all know ive been talking alot about a head swap. Well im getting more serious about it and plan on doing the swap late spring/summer of this year. Ive decided on some gt40s. I know tf heads are better but like ive said i dont need a crap ton of power, just would like a little more than what i have.plus money is a huge factor here, and even gt40s is pushing it so i dont need the tf talk. So anyhow, hear are my questions.

1: not exactly sure what pistons, but they are hypertuectic with 60 cc heads and has 10.2:1 cr. I would like to deck the heads to get around 11-12:1 cr. How much would i have to shave off to achieve this cr? Is that too high for 91 octane? Would i need octane booster? Would it even be worth it power wise?.

2: would decking that much pose problems with PTV clearences?

3: what n/a intake would work best with gt40s?

4: also, motor is. 030 over, that wont efect the heads will it?

Thanks in advance!
 

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11-12:1 is not OK with 91 octane & an iron head. Unless you've got a dome piston with a 60cc head, compression is not going to be 10.2:1. The normal flat top piston in a 302 usually yeilds around 9-9.5:1 with a 60cc head, which is perfect for a street Stang! The Explorer 5.0 intake works well with the GT40 or P heads, make sure you swap out the valve springs with some Trick Flow or Alex's spring kit.
 

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Why not have a Fox?
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5,798 Posts
Discussion Starter · #4 ·
How do you know the CR if you do not know the pistons?
Because the po told me it was. I know its just hear say but iy know this guy well so i take his word for it. Here is EXACTLY what he said when i asked what pistons are in it. Quote: "i dont know the number but they are a 10.2:1 cr with 60 cc heads." So im assuming theyre dome
 

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Why not have a Fox?
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5,798 Posts
Discussion Starter · #5 ·
The Explorer 5.0 intake works well with the GT40 or P heads, make sure you swap out the valve springs with some Trick Flow or Alex's spring kit.
I knew the exporer one works, but my car is carbed soooo, unless they make explorer intakess for carbs i need another opinion. I have a performer 302 right now but its cracked so need to replace it any how. And what better time to do it then when i swap heads? And the stock heads have a fairly new trickflow spring kit in them that ill swap over
 

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Exhaust fume addict
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Wieand stealth seems to be a popular carb manifold.

As far as shaving the heads goes. Check the PTV now and subtract the minimum safe nber from it. Safe is usually around .080 on intake and .100 on exhaust. Subtract that from current PTV
 
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