Re: plating on Exhaust manifolds and risers ?
Well, there actually is a "plating" for cast iron manifolds. I am not sure it would work to reduce corrosion in a marine manifold though.
I bought a new set of manifolds for my Ford Y-block and had them ceramic coated (inside and out) at
Performance Coatings in Auburn, Wa. They came out absolutely beautiful.
I did not ask them about coating marine manifolds. I suppose they could but the manifolds would have to be new and clean, bare metal. I don't know if they would guarantee anything or even recommend doing a marine manifold but you could ask them.
Cheers,
Rick