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GT 40 HEADS

  • Thread starter Thread starter pancho55
  • Start date Start date Dec 20, 2004
P

pancho55

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Dec 14, 2004
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Houston, Tx
Dec 20, 2004
#1
  • Dec 20, 2004
  • #1
Thinking of putting som e original cobra GT40 heads on my '68 mustang w\302. THese are originals not knowk off p heads. Heard their might be some plug clearance issues and header issues. Does anybody have any experience with this?
 
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D.Hearne

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Sep 29, 2000
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Dec 20, 2004
#2
  • Dec 20, 2004
  • #2
No clearance issues with those GT40's. Only with the "P" heads is there a problem.
 
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D.Hearne

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#3
  • Dec 20, 2004
  • #3
But before bolting them on, check your piston comp height and if they're dished. You wouldn't want to lower the comp ratio in doing the swap. The Cobra GT40 heads ( the one's that actually came on the Cobra Stangs) had 62 cc chambers. The 68 302's had either 54 cc ( J code) or 58 cc heads. You'd need to run flat top pistons with the cobra heads with as close to zero deck height as possible. Milling the Cobra heads isn't recommended either as Ford milled them from the start at the factory, then again by an outside contractor before they were assembled on the motors.
 
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pancho55

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Dec 14, 2004
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Houston, Tx
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#4
  • Dec 20, 2004
  • #4
GT40 heads

Thanks, these have been ported and polished and I am not sure of the specs on it. I am taking them to a machine shop to get them cleaned and Magna Fluxed. Will keep every body informed of how it goes. These are going on with a performer inatake and a 600 cfm carb.
 
D

D.Hearne

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#5
  • Dec 20, 2004
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Performer or Performer RPM? They'd work better with the RPM
 

DarkBuddha

Founding Member
Dec 11, 2001
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Seattle & Tampa
Dec 20, 2004
#6
  • Dec 20, 2004
  • #6
pancho55 said:
Thinking of putting som e original cobra GT40 heads on my '68 mustang w\302.
Click to expand...
Do you mean original as in Ford late model GT40 heads like from Cobra Mustangs, or do you mean original as in '60s vintage GT40 heads? If they are vintage, they might be worth some cash to the right people...
 
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pancho55

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Dec 14, 2004
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Houston, Tx
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#7
  • Dec 20, 2004
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GT40

Late model Cobra cast number F1ZEE.
 

DarkBuddha

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Dec 11, 2001
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Seattle & Tampa
Dec 20, 2004
#8
  • Dec 20, 2004
  • #8
pancho55 said:
Late model Cobra cast number F1ZEE.
Click to expand...
Not worth the coin vintage heads bring, but still damn good heads, especially for the money.

Good luck!
 
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