# Exhaust manifold gaskets



## Charlescady (Dec 13, 2015)

I'm putting Ram Air manifolds on my 400. Can anyone recommend what gaskets to use?


----------



## 69_RA-IV (Oct 6, 2015)

I ordered the Fel-pro gasket that Ames sells when I ordered the RA IV manifolds from them. It sealed up great. No complaints.

Are you getting the 2.25" manifolds (like stock) or the 2.5" manifolds that Ames is selling? I went with the 2.5" manifolds to hook up to the 2.5" custom exhaust.

Just a suggestion, if you are buying them new they come uncoated, so you can put them on and let them rust or coat them. Your options are ceramic coating (which is expensive) or VHT Header coating. Ames did carry an Eastwood product for manifold coating, but Eastwood changed the color, so they changed product. They just switched over to VHT Header Coating, specifically SP998 (Nu-Cast). Just clean off the grease and wax (of which there was surprisingly a lot of for brand new castings), mask off the mating surfaces, paint and bake. The coating turned out really well, but we'll see how it holds up.

Also, don't forget to order the flanges and manifold bolt locks. I also bought a fresh seat of manifold bolts.

Way more info than you asked for...sorry. Just went through all of this the last couple weeks.


----------



## Goat Roper (Oct 28, 2014)

Use new manifold bolts, torque to 40 ft. lbs. and make sure to use anti seize on them so you don't have one break removing them down the road.
If you are going factory correct order the metal gaskets, if not go with the Fel Pro set.
I used the original metal and sprayed them with copper coat hi temp sealant.


----------



## BearGFR (Aug 25, 2008)

I use these on my round-port heads:

PONTIAC Header Exhaust/Manifold Gasket

Best there is, in my opinion.

They also make them for D-ports:

PONTIAC Header Exhaust/Manifold Gasket

If you're not concerned about 100% factory original, I'd also recommend replacing the two outer bolts with studs. That'll make it SO much easier to deal with if you ever have to r&r the manifolds with the engine in the car.

Bear


----------



## Charlescady (Dec 13, 2015)

Thanks for the replies. 
I have a friend that had a set of original manifolds in good condition that I am using. My understanding is that the factory made both 2 1/4 and 2 1/2. . . is that true? Mine measure 2 1/4 inner diameter and 2 1/2 outer. I'm assuming these would be considered 2 1/4? 

I ordered new bolts and will use anti-seize. 

I like the looks of the metal gaskets, but I really, really don't want any leaks.


----------



## 69_RA-IV (Oct 6, 2015)

Goat Roper said:


> Use new manifold bolts, torque to 40 ft. lbs. and make sure to use anti seize on them so you don't have one break removing them down the road.
> If you are going factory correct order the metal gaskets, if not go with the Fel Pro set.
> I used the original metal and sprayed them with copper coat hi temp sealant.


Another torque spec - Fig 8-17 in the manual shows 25 ft/lbs from the flanges to the manifold, and I hate to contradict you, Goat Roper, but the manual calls for 30 ft/lbs manifold to heads on Pg 6-77. Wallace Racing states 40 ft/lbs manifold to heads - Wallace Racing - Pontiac Bolt Torque Values . We split the difference @ 35 ft/lbs



Charlescady said:


> Thanks for the replies.
> I have a friend that had a set of original manifolds in good condition that I am using. My understanding is that the factory made both 2 1/4 and 2 1/2. . . is that true? Mine measure 2 1/4 inner diameter and 2 1/2 outer. I'm assuming these would be considered 2 1/4?
> 
> I ordered new bolts and will use anti-seize.
> ...


What you have are 2.25" manifolds. If you're installing used manifolds I'd highly suggest blasting them clean, and then de-greasing and coating as I described before. They'll look brand new.

According to the techs @ Classic Reproductions (the only people reproducing the manifolds I'm aware of) they were only available in 2.25". They are reproducing a 2.5" version so people can opt to use it with bigger high performance exhausts.


----------



## Charlescady (Dec 13, 2015)

If you're not concerned about 100% factory original, I'd also recommend replacing the two outer bolts with studs. That'll make it SO much easier to deal with if you ever have to r&r the manifolds with the engine in the car.


I like this idea. Thanks.


----------



## Charlescady (Dec 13, 2015)

Thanks for the info on the 2 1/4 vs 2 1/2.


----------



## geeteeohguy (Feb 2, 2008)

Have used the stock metal gaskets on three cars with these manifolds and no leaks at all.....and manifolds have been in service for 7-12 years.


----------

