I've got a set of RM manifolds & risers but I need a 3" spacer. The RMs are dry joint so could I use the OEM Merc spacers that I already have. Other than headers and proprietary designs like Stainless Marine, are most other aftermarket manifolds & risers cross-compatible?

Almost nothing is compatible between exhaust manufacturers. I don't know if the merc spacers will fit with Rev marine stuff. I doubt it.

I have been wondering the same thing.

I have a set of marine power manifolds and am under the understanding that th EMI are a copy of these. Can anyone tell me otherwise. I would like to get so SS risers.

Sory didn't mean to hijack....I will delete if you want me too.

BuB, no need to delete, all info is welcome.

So if nothing is compatible, that means that you always have to go back to the manufacturer of the exhaust for gaskets? Cuz I'm thinking that would be an easy way to see what is compatible...manifold to riser gaskets.

???

Gil marine, Mercury Hi-performance, and Power torque manifolds share the same gaskets. Imco is it's own, Stainless Marine is it's own. And many of the early EMI, Rev, Kodiac, and a couple of others are from the same original OEM manifolds that Kodiac offered. If your not sure you could fax us a copy of your current gasket and we could do some research for you into what exactly you manifold/riser pattern is.

When I called EMI they guy could not tell me if it would work or not but he did recommend that i get some of his gaskets and see if they line up.
I have a dry joint.

If you find one that fits please post it. I have the Revolution manifolds and need a 1 1/2" spacer between the manifold and riser to get the EX hoses to line up.

Is if acceptable to put a spacer in there?