New y-pipes, original exhaust manifolds. Donut gaskets?

[gran coupe john]

Something isn't right. Anyone know the correct way this is set up for a tight seal?

 

[Steve340]

The style of manifold you have there does not use the donut gasket. Just apply sealer to the tapered face of the pipe and bolt up tight.
They are not the greatest idea and sometimes it is hard to stop the leaks.
Do a trial fit IMO.

 

[gran coupe john]

I had it all bolted up, but did not fit tight. What kind of sealer is used to keep it sealed tight, and quite

 

[Xcudame]

Permatex Ultra Copper works OK. I think JB Weld has a product out for sealing exhaust pipe gaps/leaks but I've not tried it.

 

[gran coupe john]

Been reading different stuff out there. Is there some kind of gasket that would work?

 

[Steve340]

There is no gasket I know of. I would use high temp silicone these days.
It will need to jam up tight. Anything that sets like concrete will give you problems.

 

[gran coupe john]

Don't want to ruin the manifolds, silicone makes sense. (High temp)

 

[MoparCarGuy]

 

[gran coupe john]

Did those resonators come with car from the factory??

 

[mrmopar340]

Did those resonators come with car from the factory??

Yep.

 

[Xcudame]

With the floating flange and the two conical parts (one on the manifold and the other on the pipe) it will seal pretty good. Usually have to re-tighten the bolts after a few heat cycles. And then it will carbon up decent enough to not leak.

 

[gran coupe john]

Just looking for a quiet ride, no noise. That's because I want to hear the AM radio.

 

[Xcudame]

6x9 speakers with huge magnets bolt in really easy and sound great in E-bodies.

 

[heminut]

That's a Chevy exhaust gasket you have there! Not judging or anything, just sayin!

 

[gran coupe john]

Got the old factory speakers restored.

 

[TomIGo]

Looking at the pic in reply #8 above, it appears that the 318 had a dual exhaust in 1970. Is that always the case in a Challenger? And, what would be the correct manifold casting numbers for a 70 Challenger 318 LA engine? I have a pair I bought recently and want to compare. They seem to fit the heads correctly, so they will be used, but are from a different year. One appears to be dated 68, could not find a date code on the other.

Asking for a friend!!

 

[TomIGo]

Oh, never mind! I just found my answer on the TTI website and these appear to be correct. The document says they are for 67-76 A-body, 62-74 B-body and & 70-74 E-body. Found the info here:
https://ttiexhaust.com/Classics-Ex/MfdCastingNos-340.pdf