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Header gasket install suggestions?

  • Thread starter Thread starter MUSTANGJOE
  • Start date Start date Sep 25, 2004
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Gearbanger 101

Straight Outta Locash
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Sep 26, 2004
#21
  • Sep 26, 2004
  • #21
Header bolts should be re-tightened when stone cold, not during cool down.
 

MUSTANGJOE

Silver Stanger
Founding Member
Apr 9, 2002
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Sep 27, 2004
#22
  • Sep 27, 2004
  • #22
Im gonna give it a shot. I'm gonna completly remove the headers (unbolt it form the h-pipe also) remove the old gasket and clean it really well. Add some high temp sealer to my new gaskets (won't hurt!) and reinstall. Tighten bolts to the max then drive about an hour. Let the car cool down then retighten them again. Drive the car for 2-3 days then retighten them again and add the locks on the stage 8 bolts. Anything I missed?
 

Michael Yount

Mustang Master
Apr 10, 2002
9,039
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Charlotte, NC
Sep 27, 2004
#23
  • Sep 27, 2004
  • #23
YES!!! Once you get the headers out, put a straight edge on the header flange and see if they are completely true. They're usually not, and machining them true is a WAY better alternative than trying to pull them up tight with the bolts and a bigger gasket.
 

Henceforward

The Avatar Master
Founding Member
Jul 17, 2001
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Sep 27, 2004
#24
  • Sep 27, 2004
  • #24
1415 felpro

1415 Felpro

I am running these, and I have had no problems. After my install maybe 6 months or so, the bolts were backing out a bit. I bought some Loctite Red and solved that problem.

You can pick the 1415s up from Summit.

Be sure and re-tighten the bolts after a few heat cool cycles.
 

Gearbanger 101

Straight Outta Locash
20+ Year Stangneter
Aug 10, 2002
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Ontario, Canada
Sep 27, 2004
#25
  • Sep 27, 2004
  • #25
MUSTANGJOE said:
Im gonna give it a shot. I'm gonna completly remove the headers (unbolt it form the h-pipe also) remove the old gasket and clean it really well. Add some high temp sealer to my new gaskets (won't hurt!) and reinstall. Tighten bolts to the max then drive about an hour. Let the car cool down then retighten them again. Drive the car for 2-3 days then retighten them again and add the locks on the stage 8 bolts. Anything I missed?
Click to expand...
Do not crank them right down to start. Tighten them enough that they're fairly snug and they seal, but don't squish the $hit out of them. You still want a little lee-way to work with when re-torqueing them after cool down once the headers have heat set.
 

MUSTANGJOE

Silver Stanger
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Apr 9, 2002
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Sep 27, 2004
#26
  • Sep 27, 2004
  • #26
What if I go to an exhaust shop, will they be able to straighten them out? Oh yeah, I tried that lock tight and it did'nt work thats why I invested on some stage 8, wich I think is a pretty cool invention!
 

Michael Yount

Mustang Master
Apr 10, 2002
9,039
6
79
Charlotte, NC
Sep 27, 2004
#27
  • Sep 27, 2004
  • #27
The best an exhaust shop is gonna be able to do is perhaps heat them and maybe use a press to try and staighten them - that will only work if they get lucky, and could make them worse.

Have you checked them yet? A machine shop is the way to go - they'll put them in a milling machine and take a couple hundredths off to true them up. They'll seal the first time out, and it's likely you won't have bolts backing out.
 
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