C3 Exhaust Flange Gaskets and Inserts

[Jack O.]

Hi SMEs,

I've read a lot posts on this topic but nevertheless still have questions. Not sure it matters but I'm working on a '69 BB sidepipe car.

I've owned several and as a result have two sets of what appears to me to be steel flange gaskets. These are not like the sintered metal gaskets I can get at the parts store now. Am I correct that these are some type of solid metal and were these originally used?

I also have one pair of what I'll call "inserts" that the gaskets go on and then get inserted into the sidepipes. So my overall question is, what's my best option to use? I believe I read the recommendation to use the sintered metal with the inserts but wanted to double check.

Thanks!

Jack

[Joe L.]

Re: C3 Exhaust Flange Gaskets and Inserts

Hi SMEs,

I've read a lot posts on this topic but nevertheless still have questions. Not sure it matters but I'm working on a '69 BB sidepipe car.

I've owned several and as a result have two sets of what appears to me to be steel flange gaskets. These are not like the sintered metal gaskets I can get at the parts store now. Am I correct that these are some type of solid metal and were these originally used?

I also have one pair of what I'll call "inserts" that the gaskets go on and then get inserted into the sidepipes. So my overall question is, what's my best option to use? I believe I read the recommendation to use the sintered metal with the inserts but wanted to double check.

Thanks!

Jack

Jack-------


There are two gaskets used on the right side and one on the left side. The gaskets that install between the pipe and the manifold on the left side is actually called a "packing". Originally, these were some sort of asbestos composition material. They are still available in some sort of composition material but I suppose something has replaced the asbestos. I do not recommend these. The sintered iron packing is better.

In the right side there is a flat gasket between the manifold and heat riser. A packing as described above is used between the heat riser and the exhaust pipe.

It is necessary to use the inserts (actually called "extensions") in the exhaust pipe to properly locate the packing and prevent their displacement.

[Jack O.]

Re: C3 Exhaust Flange Gaskets and Inserts

Thanks Joe. Do you know if there ever were any packing made of steel as I described. They certainly appear to me to be some type of regular metal.

[Joe L.]

Re: C3 Exhaust Flange Gaskets and Inserts

Thanks Joe. Do you know if there ever were any packing made of steel as I described. They certainly appear to me to be some type of regular metal.

Jack------


Well, the "sintered iron" packing may appear like steel. There was never any that I'm aware of that were true steel. The 2-1/2" sintered iron packing was GM #3768711 but it's discontinued without supersession. An equivalent is available under Fel-Pro #60986.

The "triangular" gasket between the heat riser and the manifold was last GM #3981068 but it's also discontinued. It's available under Fel-Pro #60117.