5.0 L MPI needing a few more hP

[73dorefan]

I have a 2005 SD 217 Hurricane deck boat with a mercruiser 5.0 L mpi sterndrive. GPS speed is 49 mph at 5000 RPM. 19P x 14D SS Prop, 1.47 gear ratio. Mfrs recommended RPM is 4600-5000. Can anyone suggest something not too difficult or expensive to add a few hp. I'd like to get my top in close to 55. I understand fairly well the science of selecting the prop and realize I will need to increase prop pitch to get more speed, but I have no idea the best, easiest and most economical way to get the additional HP.

 

[Tail_Gunner]

Re: 5.0 L MPI needing a few more hP

Prop forum's Merc Enertia prop, with mpi it's just to difficult to hop up a motor in a boat, not even speaking of the exhasut or the restrictd cam selection. There wired pretty tight from the factory......but i guess you could supa charger it or put a blower on it.........RP no pic's plz...........

 

[Reel Poor]

Re: 5.0 L MPI needing a few more hP

Don't we already have a thread about blowers?

 

[John_S]

Re: 5.0 L MPI needing a few more hP

That is decent performance for a deck boat. As gunner said, not much you can do for an MPI. Props might get you a 1-2 mph. Enjoy the good running boat, and years down the road when its time to repower go 5.7MPI.

 

[QC]

Re: 5.0 L MPI needing a few more hP

Yeah, my calcs say you need 60 more bhp for 5MPH . . . Not gonna happen. However, you may pick up 1 or 2 MPH by going to a 21 inch, but your hole shot will suffer. Also, get as much weight out of her as you can and fiddle fart around with shifting weight aft until you can go full trim and she just starts to porpoise. If you can't make her porpoise now, you can probably make her faster as is. Once you get her to porpoise at full trim, then come back here and we'll help you with that . . .