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How do you seal your exhaust manifolds/headers ?

kiwigtx

Henchman #4 and Jack-Stand Racer #2
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I want to hear all the varying opinions on the best way to seal heads to exhaust manifolds - whether it be cast iron or aluminum heads, and headers of cast manifolds.
Some say use gaskets, others say no ...some use a sealant while others don't.

Give your opinions hear on your proven combination of good sealing of the exhaust.

Pictures and details would be an added advantage to all here for future reference.

I have always used gaskets, and usually use a sealant - Hi-temp fuel resistant RTV type product...not always successful over time. however, if a car sits for long periods, that may be what causes the failure.
 
One vehicle has original cast iron manifolds. Engine swapped. Reattached exhaust manifolds, no gasket. Seals just fine.
Other vehicle has headers. Place a 1/16" diameter bead of high temp. RTV on the header around each exhaust port. Let it cure. Attached header, no leaks.

Years ago, had a SBM with headers. Used the compressed cardboard looking gasket. Leaked after 15 min. running. Never sealed.
 
Hi temp rtv (no gasket), Sanderson headers cast iron heads....no leaks in 3 yrs...
 
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I have just the felpro exhaust manifold gaskets that came in the over haul kit under my tri y headers. the {Schumacher multi layer header gaskets ended up with a tick/leak after about a week } and yes I do re tighten them after a couple heat cycles, the fel pros have been on a month now and no leaks.
 
Manifolds - spray copper, no gasket. Headers - hit the flange with a longboard, spray copper on flange and gasket, tighten snugly, run engine to operating temp, cool.down, 're-tighten.
 
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Felpro gaskets no leaks been on since 06. Everything is original to this engine if that makes a difference it may or may not.
 
Manifolds with gaskets, no leaks. I did need to add some high temp RTV to the manifold connection to the exhaust pipe to fix a leak there (only on driver side).
 
x3 on remflex. very spendy, but worth it if your metal is even the slightest bit warped.

btw, what would a ***** whale love to have??





















...a nice tight, seal. :rofl:
 
Percy's for the header to head then a copper gasket on the flange. I've been running the same ones for 4 years, even after having the exhaust apart several times they're still sealing with no sealants. What's most important IMO is a good header with thick flanges on both ends.
 
Copper gasket on the headers and aluminum on the collector.
 
With headers I use a graphite gasket. The cheapo papers tend to blow out after a while. Others here have mentioned Remflex, I've also used BBK and OBX graphites with equally as good results.
 
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