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Marine 350sbc

I have a brand new 350 chevy motor that a buddy had built for a boat of his. motor never went in, now I have it. I want to put it in a car. what all do I need to change?

I wonder if it rotates in the correct direction?

Thanks olds.
its just a block with heads, and cam (crank/pistions) Anything need changing in the water system? I have not delt with marine stuff before and want to make sure nothing is differnt for street driving. Perhaps the cam is ground to make power at a rpm not suitable for the street, ect.

Marine cams typically are ground to optimize marine applications and are not the same as street grinds. And if the engine does rotate in the wrong direction it’d have a camshaft to match.

You’d want to know things like compression ratio and cam specs. Cooling system would be different, but not internally to the block or heads.

If two of these engines are used (in a boat with props) you would want one turning one way and the other opposite. Perhaps this rotation issue is taken care of in the outdrive but cams have been ground for rotation direction modification.

Marine motors like yours are automotive motors at heart. You do need to know if the motor is made to rotate in one directon or the other. The water system for fresh water marine motors basically a separate water pump driven by the accessory belt to supply the water to the normal automotive type water pump. Inside the block the water system is the same. Salt water systems are different primarily in the materials used to reduce the corrosive effects of the salt.

The electricals, alternator, distributor, starter, etc. are designed to reduce sparking which can cause an explosion if gas fumes are present. The carburators are different, but you can easily select a carb and matching manifold of your preference.

The distributor will likely not use a vacuum advance. On a car you’d want a different distributor with a vacuum advance.

The cam timing might be a bit different but I’d leave it alone unless the motor was specifically built for marine racing. Racing motors don’t need to idle well, and a marine racing cam would be too hot for most street cars or a PU truck. If it isn’t a racing motor it should idle fine at about the same rpm as a car or truck.

If you don’t have to change out the cam this should work pretty well for you. You simply add the auto parts you need to complete the motor; starter, carb, distributor, etc.

Marine exhaust systems are very different. I think you should just confirm you can match the exhaust manifolds for a car/truck onto the block. This shouldn’t be a problem, but something I’d suggest researching before you get too deep into this project.

I remember reading an article in a hot rod automobile magazine about a mechanic who installed a Chevrolet v-8 in a Corvair. A Chevrolet Marine V-8 had to be used because it rotated in the proper direction to match the rotation of the original Corvair engine, while the Chevrolet V-8 built for cars and trucks rotated the wrong way. The rotation may be oppposite for the marine engine.

is there any way to tell left hand from right hand rotation engines?


laughs thanks again.

check torque specs for rod and main bearings. I believe they’re looser for marine applications.

Ask your buddy if it was an automotive motor purchased from Chevy, or a marine engine from maybe Mercruiser Marine ( I know they use Chevy blocks). It may make a difference. In either case ask your buddy for any and all info on what was done, and whether he knows about the rotation. Years ago(1979) I pulled a Mercruiser 260 Basically a Chevy 350 out of my dads boat and bolted in a built Chevy 327. Since the boat was already set up for the freshwater cooling system (radiator and all) it was a direct fit. Yours may differ.

I’m on my own there, He didn’t know anything about engines. He had it taken out and redone, but ran out of money or interest or something before it went back in.