[shoeman68]

Any advise when replacing exhaust manifold gaskets on a 1968 400 non-R/A non-H/O?

It seems there are only 4 bolts holding on the manifold. Do four bolts create enough of a seal?
Are paper/cork gaskets better than metal?

Thanks for any input

[goatless]

My advice- Don't use the steel or the paper. Get a set of the good composite gaskets from Fel-Pro or Mr. Gasket. I've never had any leaks using them. They have a steel core and a material on both sides that compress' to seal up minor imperfctions.
Last time a did a set of exhaust gaskets I used the original style steel gaskets based on someone's advice and they leaked right from the get-go.

[Mr. P-Body]

If the manifold surfaces are "flat", the shims are the way to go. Have the manifolds resurfaced if they're not flat (within .003"). The 4-bolt retention seemed to work well in stock engines. The factory used NO gaskets.

Jim

[Steveski]

Agree that the manifold surfaces must be absolutely flat and level or resurfaced to achieve same. Over time the center cylinder manifold tubes warp outward from the heat. I used a set of thin steel gaskets as (I was told) they would dissipate heat.

[SWEETJUDGE]

resurface to make sure you are not warped this is common

[shoeman68]

Thanks for answers. I'm not going to resurface, I think I'll go with the Mr. Gasket type as suggested. I have 108,000 original miles.
Does anyone think the bolts will snap based on experience. I did the right side and the bolts came out fine.

[68pl]

On my 68 Lemans I have 6 bolts per side.

[motorcitymusclecar]

Originally Posted by shoeman68

Any advise when replacing exhaust manifold gaskets on a 1968 400 non-R/A non-H/O?

It seems there are only 4 bolts holding on the manifold. Do four bolts create enough of a seal?
Are paper/cork gaskets better than metal?

Thanks for any input

The original cars had the metal gaskets - and they have a crush ring to seal good - i would think that anything that was not metal would burn up pretty fast since they get so hot. All the gaskets are available at the local autoparts store - may have to wait for a day for them to come in.

[motorcitymusclecar]

if you are going to replace the bolts make sure they are grade 8 because after they heat cycle a bunch of times and rust over the years you will still be able to get them out - the cheap grade 5 or three can rust over time and when you go to take them out break off then the fun begins.

[engineer]

anti seize on new bolts and proper torque.