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Installing GT40P heads on 109k block

  • 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 have a stock engine block currently with 109k miles on it. I want to put a set of GT40P heads on there. Is this a good idea, i have heard negatives from this, and others say it will be fine. Has anyone else here slapped on some performance heads on a rather higher mileaged engine? Help me out with some opinions please.
 

_jb_

New Member
Mar 4, 2004
808
0
0
Michigan, Berrien County
Jun 26, 2004
#2
  • Jun 26, 2004
  • #2
109k miles is nothing for these 302s. There are many 5.0s out there running strong with 200k+ miles. As long as the crap wasn't beat out of them, they should be fine.
 
H

hbk_136

New Member
Feb 28, 2004
194
0
0
Southeastern GA
Jun 26, 2004
#3
  • Jun 26, 2004
  • #3
how many miles does your stock block have on it, since you are putting heads on it as well?
 

5spd GT

"the 5.0 owns all"
Founding Member
Aug 7, 2002
9,516
6
99
Arkansas
Jun 27, 2004
#4
  • Jun 27, 2004
  • #4
I have a 142k on my 93 shortblock...and in 2 weeks I'm installing AFR heads, FTI cam...and all that and I'm not worried about it...

Your car ain't even broke in yet...what are you talking about ...

Seriously...you will be fine
 
8

85GTlover

New Member
Mar 20, 2004
704
0
0
Jun 27, 2004
#5
  • Jun 27, 2004
  • #5
You have ported E7's! you might not feel that much difference unless the gt's are ported to. The ones you have are supposed to be way better than stock.
 

Michael Yount

Mustang Master
Apr 10, 2002
9,039
6
79
Charlotte, NC
Jun 27, 2004
#6
  • Jun 27, 2004
  • #6
Mileage alone is no indication of the engine's condition. I've seen relatively low mileage motors that are shot; and high mileage motors that are in fine condition. The wise thing to do would be to run cranking compression and/or leak down cylinder pressure tests on it before you mod it. That way you'll know that you're gonna get the most out of your new heads (and other mods) before you bolt them on. Nothing worse than spending all that money only to find that the short block is underperforming, and at some point you're gonna have to pull it all off to refresh the short block. Don't simply guess at the condition of your short block - run the proper tests so you have some certainty.
 
H

hbk_136

New Member
Feb 28, 2004
194
0
0
Southeastern GA
Jun 27, 2004
#7
  • Jun 27, 2004
  • #7
Yes but i was going to get a killer port job on the GT40P heads from thumperoforangepark.com so it will kick ass.
 

_jb_

New Member
Mar 4, 2004
808
0
0
Michigan, Berrien County
Jun 27, 2004
#8
  • Jun 27, 2004
  • #8
I have 108,2XX miles on my car. I'm not worried about putting any mods on...unless I was thinking about NOS or something like that.
 
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