Header Gaskets

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Doppleganger

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Got ready to install my headers and realized the gaskets I had were some cheap fiber ones that came with the headers. Was wondering what you fellas used that worked. Fel-pro? Copper? etc.

I have Edelbrock E-Tec (vortec style) heads and anything I saw that looked interesting never mentioned anything vortec.

THX
 

legopnuematic

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Remflex is what I will be putting on my 76, have a remflex manifold gasket on my slant six in the dart and it sealed things up tight.

Only issue with them is being graphite they are fragile, for the long slender slant six gasket it took 4 tries to get one not broken in half.

My 76 previously and my 79 has those dead soft aluminum layered gaskets and those seem to work well too.
 

fast 99

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When I was a crewmember on a race team we used a thin bead of high temp silicone on both sides of gasket. Applied sealant then waited 10-15 minutes to solidify a little bit. Never had a leak issue. These were high dollar headers with a thick flange. Your millage may vairy.

Have headers on one of my personal vehicles. Always check for loose bolts once a year.
 

Dutch Rutter

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I've posted this before around here somewhere. When I redid the 350 in my k20 I used the remflex gaskets top and bottom, then the proform wedge locking header bolts. Had great results. These were also used on a set of old flowtechs on aluminum heads, so if they could seal that they'll work really well on higher grade stuff.
 

Bextreme04

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I'll put in one more vote for Remflex... they really can't be beat. I have them on my 350 and my LS motor with headers. No leaks at all.
 

nvrenuf

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Header flange thickness is directly related to gasket sealing success. Thin flanges can get warped easily, thick flanges seal better for longer.

My Sanderson’s have 3/8” flanges and seal great with Permatex Ultra Black.
 

Doppleganger

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So I call Summit - they ask me what I'm working on. I tell them I'm looking to buy a decent set of header gaskets for a SBC. Before I can tell them the PN I looked up, guy suggests....Remflex. lol So I ordered the Remflex header and collector gaskets yesterday. They are out for delivery today.

Thanks fellas!
 

TotalyHucked

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I'm now on my 3rd set of MLS gaskets with my Speed Engineering headers and they leak. 1st set lasted a long time, 2nd and 3rd leaked almost immediately. The flanges are good and thick but I guess they've warped by now. I think I'll give RemFlex a try for the next ones
 

Bextreme04

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I'm now on my 3rd set of MLS gaskets with my Speed Engineering headers and they leak. 1st set lasted a long time, 2nd and 3rd leaked almost immediately. The flanges are good and thick but I guess they've warped by now. I think I'll give RemFlex a try for the next ones
I just put a set of the speed engineering long tubes on my suburban and the back bolt was broken off the passenger side. I couldn't get anything in there to extract it and it's getting the 6.2 put in it in a few weeks anyways, so I said screw it. Remflex gaskets and ICT billet header bolts and torqued the bolts all to the recommended remflex torque spec... zero leaks. None of the bolts have loosened up or broken either. I put the exhaust in because I figured the 6.2 wouldn't do too well with the tiny 5.3L stock exhausdt system and wow what a difference. 1-3/4" long tubes to 3" high flow cats to a single 3.5". Then a flex pipe, 3.5" resonator, and single 3.5" flowmaster 50 series Big Block muffler. Fuel trims almost immediately went to +20, so I'll need to do some tweaking on the tune to take advantage of the extra efficiency, but it has quite a bit more roar during acceleration and no resonation or excessive loudness at cruise.
 

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