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  • SN95 4.6L Mustang Tech

Header Gaskets..what to use

  • Thread starter Thread starter ZIncGTSTANG
  • Start date Start date Jan 31, 2007

ZIncGTSTANG

New Member
Jun 28, 2005
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Jan 31, 2007
#1
  • Jan 31, 2007
  • #1
I'm about to put SLP lt headers on my '03 GT but am unsure which gaskets to use. I have read that many people say to not use the gaskets that came with the headers. I have also read that some people reuse the stock ss ones. Anyone know how good the SLP gaskets are? Did I pay for good gaskets or just good headers. Also heard that some people double up the old gaskets with the new ones. All of those that have installed headers, what did you guys use?
 
I

Invictus

New Member
Jan 26, 2007
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Jan 31, 2007
#2
  • Jan 31, 2007
  • #2
i used the compressed fiber ones that came with my BBK LTs and they were absolute ****. right out of the garage i had major leaks. bought some copper ones from SUMMIT (i think they were around 60-70) and immediately, problem fixed along with a noticeable performance gain.
 

ZIncGTSTANG

New Member
Jun 28, 2005
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Jan 31, 2007
#3
  • Jan 31, 2007
  • #3
Invictus said:
i used the compressed fiber ones that came with my BBK LTs and they were absolute ****. right out of the garage i had major leaks. bought some copper ones from SUMMIT (i think they were around 60-70) and immediately, problem fixed along with a noticeable performance gain.
Click to expand...

Exactly what I dont want-a gasket leak after I get all the bolts tightened down. Ill check out summit. Those are pretty expensive gaskets.
 
T

TGJ

New Member
Mar 30, 2005
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Jan 31, 2007
#4
  • Jan 31, 2007
  • #4
Percy's Dead soft header gaskets or new Ford OEM ones( not FRPP/SVO header gaskets )
 

blackink00

I missed a shift & stole Curt's money.
Mar 30, 2005
545
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0
Tempe, AZ
Jan 31, 2007
#5
  • Jan 31, 2007
  • #5
just get some copper ones from summit and the stage 8 locking header bolts. dont know aobut the ones that come with slp. i know jason86 used them on his car and i havent heard any problems with it yet. might wanna PM him
 

jivepepper

Founding Member
Jun 19, 2002
776
5
18
Under a Sombrero. in WV.
Jan 31, 2007
#6
  • Jan 31, 2007
  • #6
I reused my stockers and stock studs, on a cheap set of used macs. Its been 7months later and still no leak.
 

ZIncGTSTANG

New Member
Jun 28, 2005
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Feb 1, 2007
#7
  • Feb 1, 2007
  • #7
Thanks for the replies everyone. I've heard good things about the Persy's dead soft from summitt, but haven't really heard the reason for them being good. I was thinking about getting the FRPP ones, but they're only $15...price scares me. The SLP gaskets that came with the headers run $30 and seem like they would form fit alot better than copper/ss gaskets. The ford gaskets also cant really be damaged during install and are dependable on stock manifolds. Maybe I am worrying too much. I just don't want to do this twice right after I finish.
 

ZIncGTSTANG

New Member
Jun 28, 2005
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Feb 1, 2007
#8
  • Feb 1, 2007
  • #8
Here's a shot of the gaskets.
http://i116.photobucket.com/albums/o21/03zincGT/SLPheaders012.jpg

I think I'm just going to go with new ford gaskets because I haven't really heard much about the slp gaskets and everyone that gets mac or bbk says their gaskets suck.
 

LaserRed01GT

Banned
Oct 3, 2006
739
3
0
Clearwater, FL
Feb 1, 2007
#9
  • Feb 1, 2007
  • #9
The stock SS gaskets are not bad, but if you only want to do it once use the Percy's seal 4 good, or Cometic MLS.

The Percy's work so well because they conform to the un-true surfaces of the header flange and because the gasket is solid, it cannot blow out.

Percy's# 66033 Ford 4.6 2-Valve 1.625" Round

Don't use those POS gaskets that come with the headers.
 

'01 Steed

Founding Member
Aug 2, 2002
482
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16
Michigan
Feb 1, 2007
#10
  • Feb 1, 2007
  • #10
OEM's with no issues.

Of course, header flange quality needs to be considered. Hooker may be a bit better at controlling flatness than other makers.
 

gtvertsoon

New Member
Apr 17, 2005
154
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0
Port Tobacco, MD
Feb 1, 2007
#11
  • Feb 1, 2007
  • #11
I originally used the stock ones since they are metal. The passenger side leaked so I pulled it apart AGAIN and used a fel-pro gasket from autozone. Together with some silicone gasket maker, worked like a charm and you don't have to retorque the bolts because the silicone holds them.
 
C

comporange04GT

New Member
Jun 19, 2005
110
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0
Feb 1, 2007
#12
  • Feb 1, 2007
  • #12
I used the Bassani gaskets that came with my headers and haven't noticed any leaks. I don't think that I would double up headers gaskets.
 

ZIncGTSTANG

New Member
Jun 28, 2005
34
0
0
Feb 1, 2007
#13
  • Feb 1, 2007
  • #13
I've heard of almost all the header gaskets in here leaking or blowing out on one or more occasions. I think the leaks and blowouts are probably just from people messing up during the install by not tightening the bolts enough, overtightening them, or tearing the gaskets. I think Im just gonna go with new ford ones. Thanks for the replys. Every gasket thread I read, everyone has mixed opinions on what to use.
 

hotmustang331

Active Member
Apr 29, 2004
2,967
3
48
Bastrop,TX
Feb 1, 2007
#14
  • Feb 1, 2007
  • #14
^Exactly. I used the gaskets that came with my BBK LTs and they worked leak free for the 6 or so months I had the headers on. But the guy above a few posts had leaks right off the bat. Perfect example.

NOW I have percys dead soft aluminum gasktes....we will see how they work tomorrow
 

foncarelli

Member
Jan 7, 2003
156
1
18
Feb 1, 2007
#15
  • Feb 1, 2007
  • #15
LaserRed01GT said:
The stock SS gaskets are not bad, but if you only want to do it once use the Percy's seal 4 good, or Cometic MLS.

The Percy's work so well because they conform to the un-true surfaces of the header flange and because the gasket is solid, it cannot blow out.

Percy's# 66033 Ford 4.6 2-Valve 1.625" Round

Don't use those POS gaskets that come with the headers.
Click to expand...


x 2 ... worked like a charm so far.
 

ADRENLN

Active Member
Apr 16, 2003
2,342
3
49
NJ
Feb 1, 2007
#16
  • Feb 1, 2007
  • #16
im useing the slp gaskets...im gonna change them though when i do the block swap in the summer. not sure if they are leaking, but i have a leak somewhere in the exhaust. i think my leaks are from the bolt up magnaflow mufflers though.
 

steveb24

New Member
Nov 28, 2005
555
0
0
wilmington, DE
Feb 2, 2007
#17
  • Feb 2, 2007
  • #17
u guys all using the stock studs/ nuts? u put some loctite on them or just tighten them real good? i wouldnt want to be tightening them all the time.. acctually.. never.
 

hotmustang331

Active Member
Apr 29, 2004
2,967
3
48
Bastrop,TX
Feb 2, 2007
#18
  • Feb 2, 2007
  • #18
I actually used anti sieze with the stock studs/nuts . No problems.

I used it on the side of my new headers....but forgot to on the pass side LOL. But being SS bolts I should be ok.
 
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