3 blade to 4 change in performance?

I have an OMC 90 hp on a 20 foot pontoon. The 13 3/4 x 15p Michigan Wheel on the boat will run out to about 5000 rpm. I'm thinking about trying one of those Comprop 15p 4 blade composite props. Would the change to a 4 blade pick me up a couple of hundred rpm's or will I have to drop down to 13?

I guess my question is, if pitch is not changed how will the 4 blade effect performance?

Re: 3 blade to 4 change in performance?

You need to drop down to a 13. Going with a 4 blade prop normally gives you a better hole shot with a bass type boat.

Re: 3 blade to 4 change in performance?

We could do a little better with your question if we had the max rpm and speed.
What year 90?Is the 5,000 with a typical load?

Re: 3 blade to 4 change in performance?

Not sure if you will like the comp prop with a heavy drag load. It will flex allot and I doubt you will see much gain.

Re: 3 blade to 4 change in performance?

The 90 is an '85, 5000 is with my usual too much fishing gear and one other POB, at just under 30 MPH.

I've had a Comprop on 2 other boats, one 17 foot Starcraft witha 90 Merc, and one 20 foot Fisher Pontoon with a 75 Merc, loved the performance from both. If they made a 13p for my OMC 90 I'd have one on right now.

Thanks for the replies.

Re: 3 blade to 4 change in performance?

Solas makes a great aluminum prop that is available as a 4-blade 13 pitch. Part # 2413-133-13 will fit your motor.

Re: 3 blade to 4 change in performance?

Yessir, I saw that and I am giving it some consideration. Part of the reason I posted is to see if the 4 blade is a good match for the pontoon.

I put a 14 foot long tube down the center of my boat last Spring and hung the 90 on the original transom. If I had it to do over I would have had a transom built into the 22 foot tube I used for the center tube, but it's too late for that now. I am getting some blowout when I get to the 30 mph mark if I don't trim the motor all the way down. I bought a jackplate to allow me to go a little bit deeper, but I still want to get the RPM's up to about 5500, or a little over.

Thanks for looking the Solas up for me, I will use that information.

Re: 3 blade to 4 change in performance?

The Solas is a good deal at $99 right here at iboats.

Re: 3 blade to 4 change in performance?

A 4 blade will combat blowout(venting).As you may have experienced it will also usually improve handling at speed and at the dock.