Also not opposed to running the bravo impeller pump on the alpha if it's possible. What would need to be changed other than the inlet hose mentioned above? I'm also assuming you have to remove the impeller from the housing within the alpha itself

Yeah remove the impeller in the alpha and route a non collapsable hose from the transom to the sea pump intake.
Also need to use the shift interrupter from the alpha setup. The older ones ground the coil, newer one may be different, cant remember, but you will need it.

Does the 350 MPI have a provision in the ecm for shift interrupt switch?

Chris

Take a look at the little magnifying glass, there are notes describing the application for each one.

The bravo version does not, that is one of the obstacles. Mercury does offer a 350 MPI Alpha engine as part of the reman program.

Awesome ! Thanks. You learn something new everyday.

If you are going to use an ALPHA GEN 2 outdrive you can NOT use a bravo impeller set up unless using a water pick up instead of the drive water inlets.

., And for all --- the Gen 2 Alpha impeller and housing is more bullet proof than any bravo housing and impeller. The alpha gen 2 impeller is called a floppy vane impeller and I have seen people never change it with the darn engine still pumping water like crazy. The longest alpha gen 2 impeller and housing ( in which is heavy duty stainless steel with a pretty thick wear plate on the bottom ) in use was 12 years straight. I could not believe it if I did not see with my eyes. I do not recommend ever doing that period. Just saying.

The Alpha impeller set up does not pump as much water volume as the Bravo set up,

Lots of good info here. Thank you everybody. I did find the Alpha and Bravo versions of the 350 Mag Mpi on mercs reman website. To me, it seems easier just to buy the engine for the correct application instead of trying to change things and make it work. If decide to do it I'll keep everybody posted through the transition process. Now for the most important question, how much speed will be gained from the old engine to the new? Boat currently runs a best of about 57mph with a carbed 350 Mag.

The interrupter switch can be added to use the Gen 2 provided your using the EST distributor. Need to change the switch from a NO to a NC switch. If motor has the HVS distributor, don't think it will work, but might, I would need to dig some more.

As for speed, it takes a lot of HP to increase above boat efficient plane speed, and will leave that to others

Play with this, it has been quite close for a few boats I work on. Single engine.

Desired Speedē / Current Speedē = Y

Y x Current HP = HP needed to go Desired Speed.