23CC Evinrude 225 WOT..

[gofastsandman]

Originally Posted by thehermit

Tried out Bigshrimpins 15.5x17 p Mirage Plus

Wow what a stern lifter!

Numbers:
3400rpm 12.3 mph- min plane
4200rpm 31.6 mph
4500rpm 34.6 mph
4600rpm 35.3 mph
5400rpm 43 mph-WOT


In the end I went back to the 15x15 sst2. I would love to hear who is using a 15p mirage plus

I tried a 17 p on my 20 w 150 and damn a stern lifting bitch she is.
Just cant turn it. LOVE that prop.

[Spruill242]

Alright guys figured I'd give an update.

Got a 15"X15 prop on the boat and got a chance today to do a couple WOT runs. Boat is now hitting 5700 at WOT and clocking in at 35 knots. Also got the trim tabs repaired. Really woke the boat up. 4000 is seeing 26 knots and 3500 is at 20. Pretty happy with the results.

Prop is a 15"X15 Solas Rubex alluminum.

[thehermit]

Nice !

[Spruill242]

Yeah I'm happy. Combination of prop and tabs really makes a difference. Would like to raise the motor up a hole but that's just being nit picky at this point.

Boat got on plane very quick. Less harmonics at WOT. Can level the boat out as needed to vastly improve ride.

Basically I'm a believer. Put the time in to get your prop right and get tabs on the boat. Very worth it.

[76Red18]

Originally Posted by Spruill242

Yeah I'm happy. Combination of prop and tabs really makes a difference. Would like to raise the motor up a hole but that's just being nit picky at this point.

Boat got on plane very quick. Less harmonics at WOT. Can level the boat out as needed to vastly improve ride.

Basically I'm a believer. Put the time in to get your prop right and get tabs on the boat. Very worth it.

Raise it, you might be even happier. The right set up will make a good hull perform correctly. Pitch and diameter of a prop matter but rake, cup and blade design will dramatically effect performance also.

[Spruill242]

I bet quality of prop can also make a difference. Especially with this one being very entry level in design. I'm happy to be at the dial in stage instead of scratching my head as to why it wasn't hitting correct rpms.

[Bushwacker]

Sounds like you got pretty close on your first shot at a prop! (Is it a 3B or 4B prop?) However before you jump to a SS prop, I'd still raise the motor another hole. Did you get a look at the AV plate while up on plane at a normal cruise speed? It's important to get the height correct before fine tuning the prop. Raising motor might give you some more rpm, but if you had a lighter than normal load you'll lose some rpm if you add weight, so load her up with some trash cans filled with sea water if necessary to simulate your max normal load and try that before spending big bucks for a SS prop. I believe Solas actually makes the props for BRP, so whatever the Solas equivalent is to BRP's 3B Rebel or 4B Cyclone would probably be a good choice. The 4B will give most stern lift and best low speed planing, and the 3B might give a little more WOT speed and mpg.

[76Red18]

Originally Posted by Spruill242

I bet quality of prop can also make a difference. Especially with this one being very entry level in design. I'm happy to be at the dial in stage instead of scratching my head as to why it wasn't hitting correct rpms.

The old omc sst was an entry level stainless prop that works great with the SeaCraft hull. It had a decent amount of cupping on the trailing edge of the blades that provided some stern lift. There's a few of those still around. Avoid the sst 2, as it has cupping on the tips that provide bow lift.
A stiletto bay pro 3 is what's on mine. It's a 4 bladed 14 1/4 x 15 with low rake and lots of cup on trailing edges and tips. Picks the whole hull up.
Another member had one of their 3 blades that worked real well also.

[bumpdraft]

When I bought my 1983 23', it had a 235 on it(in 93), it had a 15x15 prop. The same prop worked fine on a 200 Ocean runner. When I put on a 225 Yamaha ox-66 Saltwater series, I tried a couple different props. I settled on a saltwater series 15 1/2 x 19. After a test ride with a factory rep, I was able to exchange it for a 15 1/2 x 17. It was still a little over-propped, but close and I loved the way the boat rode with the prop.
I then bought my current motor, a Yam F 225. I put the same prop on it and used it for several years before getting a Solas 4 blade. Since my motor operating range is 5000- 6000 rpm (really 5500-6000) and my motor then turned 6100 rpm, I figured that was close enough. I got to thinking about it and I asked my mechanic. He told me that the motor has a rev limiter at 6100 rpm. So now I'm thinking I could be under propped. By how much, I really don't know.

[Bushwacker]

Originally Posted by bumpdraft

. . . I then bought my current motor, a Yam F 225. I put the same prop on it and used it for several years before getting a Solas 4 blade. Since my motor operating range is 5000- 6000 rpm (really 5500-6000) and my motor then turned 6100 rpm, I figured that was close enough. I got to thinking about it and I asked my mechanic. He told me that the motor has a rev limiter at 6100 rpm. So now I'm thinking I could be under propped. By how much, I really don't know.

A good prop shop could probably put a "100 rpm cup" in it that would drop your rpm and improve your efficiency a bit.