Mercruiser 5.7L Carb upgaded with 5.0L MPI

[delmarjr]

Can the Mercruiser 5.0L MPI parts be put over on a Mercruiser 5.7L carb engine of the same year and function better than using the stock carb? I have several 5.0L MPI with cracked blocks that I bought cheap at a dealer and have several 5.7L carb engines that I would like to make MPI. They are 2004 models with the ECM 555. What are the pros and cons to doing this conversion?

 

[APPALOOSA2]

Re: Mercruiser 5.7L Carb upgaded with 5.0L MPI

I don't have the answer, but I do know the ECU would be different for a 5.0 vs 5.7. The 350 needs more fuel than a 305 also you would need ALL the sensor's and the engine wiring harness to complete it.
The ECM might be the same but a different flash program for a 5.7.

 

[mrainey889]

Re: Mercruiser 5.7L Carb upgaded with 5.0L MPI

The parts should swap over pretty easily, however what has already been said is correct to the best of my knowledge, the fuel map will be wrong for the 350 when using the map of the 305. Regardless, a simple fix would be to find a place to have the ECMs you have re-flashed with the proper software, or sell them and buy ones for 350 engines.

Mike

 

[Windykid]

Re: Mercruiser 5.7L Carb upgaded with 5.0L MPI

I dont think the intake will fit. I believe carbed and any injection are different bolt patterns, But I have been wrong before.