Car engine in boat?

Question

I cracked the manifolds and block on my 305 mercruiser. Can I use a high performance 350 automotive engine block and swap the rest of the parts?

Answer 1

Yes you can swap the blocks, make sure that you have the room for the 350, some boats do not allow any extra room for a larger engine.

Be sure to use the marine ignition system, alternator and marine starter. Failure to do so could be very explosive!!

Answer 2

The HP 350 (4 bolt mains??) should drop right in.

A marine specs build engine has some different clearances in the components like truck and HD engines.

For the powerband you can swap in a marine profiled cam.

Replace the steel freeze plugs for brass.

Use non steel or aloy. (head)gaskets.

Be sure to use all the marine approved hardware from the old engine.

Answer 3

No.  Marine engines are cammed different, to change the powerband.  Also many parts that are steel on an auto engine are brass or stainless steel to control corrosion in a wet enviorment.  Save your money, it,s been tried.

Answer 4

Ford made a 305 you may check your block and see. It could be a ford 305 v8. It could be as easy as a long block and use your heads pan and intake.

Answer 5

Car engines do a lot of loafing - cruising down the hiway at 1100 RPM.  Boat motor has to hold the boat up and push it through water - the equivalent of driving uphill 100% of the time, in low gear.  It's why boats don't have transmissions.  If you don't mind running it full time at 5500 RPM, then just be aware of the proximity of the engine to the fuel tanks.  Your automotive alternator throws off sparks.

Answer 6

Im using a 454 out of a motorhome had to change the cam

but Im sure a little 350 wont give you too much trouble

Answer 7

yes with slight modifications