header gasket keeps blowing out
Thread Starter
Junior Member
Joined: Feb 2014
Posts: 5
Likes: 0
From: the land of corruption
Car: 89RCLBk1500,91bird,99grandam gt
Engine: tbi350,frankenstein tpi 350,3400sfi
Transmission: nv3500,t5,4t45
Axle/Gears: 3.42,not sure,also not sure
header gasket keeps blowing out
i have an 89 chevy truck 350 tbi that i put shorty headers on and it blew out the paper pacesetter gasket they cam with and blew out a percys performance dead soft aluminum one after that. the passenger side is fine with only paper one whats the deal
Last edited by brokencomputer; May 10, 2014 at 12:50 AM.
Supreme Member
Joined: Jun 2011
Posts: 2,036
Likes: 5
From: knoxville tn
Car: 86 IROC
Engine: 5.0 TPI
Transmission: 700-R-4
Axle/Gears: 2.73 open
Re: header gasket keeps blowing out
header bolts have a nasty habit of loosening.there are locking bolt kits,and copper gaskets that solve the problem. but first id take them off and lay a straight edge across the mounting flanges .if they aren't perfectly flat,you can have a machine shop mill them till they are. that should do it for you
Thread Starter
Junior Member
Joined: Feb 2014
Posts: 5
Likes: 0
From: the land of corruption
Car: 89RCLBk1500,91bird,99grandam gt
Engine: tbi350,frankenstein tpi 350,3400sfi
Transmission: nv3500,t5,4t45
Axle/Gears: 3.42,not sure,also not sure
Re: header gasket keeps blowing out
i seem to have gotten them to seal for right now any way put bead of hi temp copper rtv on a new gasket and put it on, seems alot better now. and yea i think i fergot to re torque after driving.
Joined: Oct 2001
Posts: 12,214
Likes: 1,140
From: Il
Car: 1989-92 FORMULA350 305 92 Hawkclone
Engine: 4++,350 & 305 CIs
Transmission: 700R4 4800 vig 18th700R4 t56 ZF6 T5
Axle/Gears: 3.70 9"ford alum chunk,dana44,9bolt
Re: header gasket keeps blowing out
1" long bolts, anti-seize on threads and a fel-pro 1405 gasket.
Supreme Member
Joined: Oct 2001
Posts: 8,113
Likes: 6
From: NWOhioToledoArea
Car: 86-FireBird
Engine: -MPFI
Transmission: T5
Axle/Gears: 3:42
Re: header gasket keeps blowing out
are they flat? header flangers are often to thin, with heat n time they don't clamp/seal well.
Last edited by Gumby; May 10, 2014 at 03:00 PM.
Supreme Member
iTrader: (1)
Joined: Aug 2007
Posts: 1,390
Likes: 0
From: Bright, IN
Car: '86 Bird, 96 ImpalaSS, 98 C1500XCab
Engine: LG4, LT1, L31
Transmission: 700R4, 4L60E, 4L60E
Axle/Gears: 3.73 Tors, 4.88 spool, 3.73 Eaton
Re: header gasket keeps blowing out
There is no gasket that will reliably seal cheap thin warp-prone header flanges. Ultra Copper RTV is your friend there.
However, if you have quality thick header flanges, then the most durable seal I've found is the embossed steel shim gaskets like GM uses for stock manifolds. You can use those and just add the hole(s) necessary for your header bolt arrangement.
Thread
Thread Starter
Forum
Replies
Last Post
