[Dragncar]

While not entirely new the annealing appears to be and that would make these copper gaskets dead soft.
I have used SCE regular copper gaskets for years with success.
While these are not cheap at 90+ $ (even the sbc ones are 60+) they are not going to blow out.
The white Mr. Gasket ones always seem to blow out after awhile. Even the Mr. Gasket- Fel Pro Race gaskets do not seem to last forever. A lot of folks like Rem Flex too.
I was going to buy some more regular copper SCE header gaskets for the new engine but I will risk another 50 bucks and try these out.

https://www.summitracing.com/parts/sce-e28286

[steve25]

Once I started coating both sides of the Fel-pro exh gaskets with Antiseize I never blew another one out even thru full exh systems and the back pressure that they have.

[Dragncar]

Well, it looks like they are only in 1.875" size.
The standard ones I bought were a full 2"

[steve25]

Your talking round port I guess?
Sorry I was referring to D port.

[mysticmissle]

I just use silicone

[b-man]

Originally Posted by mysticmissle

I just use silicone

This.

Save your money and just use high temp silicone sealer and no gaskets.

[64speed]

Originally Posted by b-man

This.

Save your money and just use high temp silicone sealer and no gaskets.

Do you use copper?

[Sirrotica]

The high dollar header manufacturers advise in their instructions to use high temp RTV.

I have a set I installed in 1988, D ports, and they are still on the engine, never leaked so far. The headers will probably rust through, before they leak at the heads. Any color you desire as long as it's high temp.

Directly from Permatex:

Specific Sealing Application Exhaust Manifolds, Thermostat Housing, Gear Housings, Valve Covers, Water Pumps

[slowbird]

Remflex hands down the best gaskets in my opinion

[b-man]

Originally Posted by 64speed

Do you use copper?

Either that or high temperature red.

[JSchmitz]

The annealing process for copper is to heat it cherry red and quench in water. Would be hard, for an individual, to do with a header gasket.

[JSchmitz]

I used Ultra Copper (no gaskets), on SBC headers, on my daily driver with no failures. I never tried it on Pontiac. Would be tough to not make a mess it seems. I use Remflex for Pontiac. I use Ultra Copper on all header bolts as tread locker. Keeps them from loosening up.

[mysticmissle]

Originally Posted by b-man

Either that or high temperature red.

i like dow 333 i think is ill have to check its clear so not quite as noticeable, ultra copper high temp red, black it doesnt matter. if your flanges are close to flat it will seal up and you will be fine. just let it skin over a bit so the mess is minimum.
I do use steel dport gaskets on the manifold cars i own.

[78w72]

never had a header gasket failure using anything from the cheap white paper gaskets supplied with some headers, have hedman headers in use for 15+ years on a pontiac 400. & mr gasket graphite type gaskets on a 500+hp for 6+ years with lots of street miles & drag strip time on both engines.... but i use header bolts with serrations under the head to help lock & most important is to retorque after a few heat cycles then check/retighten 1-2 times per season. most headers require a little effort to check the bolts to keep them leak free unlike manifolds that are basically install & forget.

[Gach]

Originally Posted by 78w72

never had a header gasket failure using anything from the cheap white paper gaskets supplied with some headers, have hedman headers in use for 15+ years on a pontiac 400. & mr gasket graphite type gaskets on a 500+hp for 6+ years with lots of street miles & drag strip time on both engines.... but i use header bolts with serrations under the head to help lock & most important is to retorque after a few heat cycles then check/retighten 1-2 times per season. most headers require a little effort to check the bolts to keep them leak free unlike manifolds that are basically install & forget.

Exactly been using the Mr Gasket white ones for over 28 years never had one blow out. Like you said got to re-tighten them. After few cycles, and make sure the flanges of flat. I love them because you can get all bolts started. Then slut the gaskets so they drop right in. My headers are a tight fit.

[Gach]

Plus the 2” header opening match's the heads and header opening perfectly.

[Gach]

Hey what ever works for you.

[Half-Inch Stud]

Graphite-composite with steel core worked best for me. They de-couple the Header Flange heat from the head too.


Summit: https://www.summitracing.com/parts/r...+5dde8e04ccb6b

O-Ports on ebay: https://www.ebay.com/itm/28531913007...Bk9SR-qQ9aWfYg