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GT40P Heads Good?

  • Thread starter Thread starter hbk_136
  • Start date Start date Jun 26, 2004
H

hbk_136

New Member
Feb 28, 2004
194
0
0
Southeastern GA
Jun 26, 2004
#1
  • Jun 26, 2004
  • #1
I was thinking about buying a pair of GT40P heads to replace my current heads. As you can see from my sig, i have a set of completely redone, ported, and milled E7 heads. Does this sound like a good move, (HP-wise)? Will these GT40P heads outflow my ported and milled E7's? Can someone out there with GT40P heads give me some feedback on their performance? I appreciate any help, :worship: :worship:
 

TrophyHead

15 Year Member
Mar 18, 2003
1,195
11
49
PA
Jun 26, 2004
#2
  • Jun 26, 2004
  • #2
www.thumperoforangepark.com Check this out.

I'f you port and polish those GT40P heads they will be great. But if you leave the GT40P heads untouched you won't gain that much more HP.
 

TrophyHead

15 Year Member
Mar 18, 2003
1,195
11
49
PA
Jun 26, 2004
#3
  • Jun 26, 2004
  • #3
My mistake Thumper was talking about the GT40X heads. But check the site out anyways.
 
H

hbk_136

New Member
Feb 28, 2004
194
0
0
Southeastern GA
Jun 26, 2004
#4
  • Jun 26, 2004
  • #4
Interesting, but right now i just need to know about GT40P heads. But thanks for the reference, i live close to orange park so i can get them to port my heads for me.
 

MustangMulch

New Member
Mar 27, 2003
303
0
0
Santa Clarita, CA
Jun 26, 2004
#5
  • Jun 26, 2004
  • #5
I thought thumper's heads outflowed stock gt40p's??
 

Michael Yount

Mustang Master
Apr 10, 2002
9,039
6
79
Charlotte, NC
Jun 26, 2004
#6
  • Jun 26, 2004
  • #6
hbk - what do your heads flow? We can't tell you how they'll compare with the P's unless you can tell us what your flow numbers are.
 
H

hbk_136

New Member
Feb 28, 2004
194
0
0
Southeastern GA
Jun 26, 2004
#7
  • Jun 26, 2004
  • #7
Yeah, that's the problem. I bought the car with them already on, i don't know the #'s. I will email the guy to see if he knows.
 
H

Horsepower67

New Member
Feb 1, 2004
62
0
0
Jun 26, 2004
#8
  • Jun 26, 2004
  • #8
I have set of "P" heads on a pretty nasty carbed 351W in my '67 Ranchero GTA. One thing, the "P" heads have smaller valves than most aftermarket heads. I think the valves are probably way too small for this engine, but it does make pretty killer power overall and revs very quickly. I do have to watch out for detonation a lot since they're iron and I'm running 11:1 compression.
 
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