Can anyone tell me if there is a difference between the two and what the difference is? I was given the price for the 350 MAG MTI but a 383 MAG MPI was installed.
Really wanting to know if I got a good deal or was I taken for a ride.
Thank you for your assistance.

What's a 350magMTI? Did you mean MPI? as in multi-port injection? The 383 has more torque and is probably a more expensive engine. I have 350magMPI's in my 28AT, they are good engines, just need more torque; i.e speed.
Let me know how you like the 383.

I have never heard of a 350 Mag MTI, I am sure it is supposed to be MPI(multi port injection). The 383 is a 6.2 MPI and is a better engine. If you payed for a 350 Mag MPI and got a 6.2 Mpi, you got a good deal!

The 6.2 is the 377, the 383 is a bored out (30 over) 377. You got a great deal.

You are correct about the 377

The only problem maybe if you paid for a NEW Merc 350 Mag and got a 383 because the Merc 383s are all rebuilt engines which I assume should be significantly cheaper.

383 sold as a quicksilver re-man. Mistake blocks punched out. You can not get the same extended warranty from merc. The package should be less $ than the 350 mpi.

http://sites.mercurymarine.com/porta..._schema=PORTAL

Same warranty, infact you can get two more years as an option. From everything I have read on the net ( take it for what you paid) nothing but good reviews.

http://http://www.speedwake.com/uplo...hlight=383+mpi