Manifold questions

[normanpitkin]

hi ,

have finally got a manifold for the 48 new yorker ,do i need a new manifold gasket for the intake manifold as well as the exhaust manifold?As i understand it ,both have to come off to fit the new manifold.Also has anyone had a manifold ceramic coated ,was it worth it? As these manifolds are so rare i think the ceramic coating might make it more durable/stronger?

[martybose]

I had my cast iron headers ceramic-coated several years ago. A very impressive drop in underhood temperature. They still look nice now; the only place it has discolored is one that got nicked by a dropping tool. Just be sure that you get them installed and run for the first time while they are really clean when the final hardening takes place.

Marty

[Niel Hoback]

If the 8 cylinder manifold gaskets are sold like the 6's are, you get both intake and exhaust, because both have to come off together.

[55 Fargo]

I had my cast iron headers ceramic-coated several years ago. A very impressive drop in underhood temperature. They still look nice now; the only place it has discolored is one that got nicked by a dropping tool. Just be sure that you get them installed and run for the first time while they are really clean when the final hardening takes place.

Marty

Interesting Marty, please explain to this neophyte, what is it about ceramic coating of the manifolds, that causes a drop in under hood temps.

My hunch is the ceramic coating insulates the exhaust pipes, allowing the hot gases and air temps to exit out the tail pipes.

Is this a near correct assertation........Fred

[JBNeal]

the ceramic coating absorbs heat so slowly that the heat in the exhaust gases escapes the manifold before significant heat exchange takes place. Aluminized exhaust pipes are similar in that they absorb heat slowly, but since aluminum is ductile, the pipes can be formed without damaging the surface coating.

[martybose]

What he said above. Essentially the ceramic coating (both inside and outside were coated) is an excellent insulator, so the header is a LOT cooler than they were when they were just painted (and starting to rust).

Marty