[Wrenchspinner]

Hey guys. Not really hot rod but....Is there any difference in a marine (mercruiser) head compared to a truck head. My boat has a couple of Mercruiser 260hp SB350 in it. I have a sealed freshwater coolant system so the block never sees saltwater. I am looking at repowering and can get a pair of rebuilt Chevy 260hp truck engines for a fraction of the cost. I am aware of the camshaft differences and am prepared for that as well as roller timing chains. The Mercruisers do NOT have stainless cranks like so many people have tried to tell me. They do have stainless head gaskets but agian I am fresh water cooled so not an issue. But the casting #'s on the heads don't match up so I was wondering if anyone might have some first hand knowledge about the heads. Oh, and they are mid 80's, all of them.

[ericnova72]

Heads are no different than car versions except they may have hardened seats in them.

I don't think there is a company in the world that makes stainless cranks, stainless would not be a good material for a crankshaft. Amazing what some people will believe and pass along as info, isn't it??

[bondo]

Ayuh,... The Standard Production motors used by Mercruiser are whatever motors GM was putting in their trucks for any given Year...

Folks do exactly what you want to do,... Everyday...
If you wanta talk Marine motors,+ whatnots,...
Come on over to iboats forums...