Originally Posted By: willix
Boat engines typically have hi-perf OEM parts and you want to be sure you are not giving any of them up. Pistons, oil systems, timing sets, valve trains, & other hard parts are commonly modified over stock specsGM, ford, Chrysler, by marine Builders such as OMC, Mercrusier, ect...
^^^^ YES. This is true. Marine 350s from what I've seen, got bigger mains, stouter crank, at the minimum. It's more of a quasi-LT1 type/truck type motor than a standard 350. Intake manifold will be different than auto-- to support marine apps for torque, not revs.
Other 8's get more radical. the 318 was often (always?) stroked for marine use, a very different running engine than in a car.
I would avoid a crate, or a shipped rebuild, from any auto application. Get a marine rebuilder involved, or a crated marine, or, a stout truck-built engine. IF you do that, tho, ensure that it is set up for the proper marine-approved components as required for fire safety.
I don't know if my 350 was cammed differently, but 4800 rpm is considered the proper WOT rpm if geared and propped correctly. different than a car. So... it could very well be cammed different.