I have a 21' Pro-Line w/a Cuddy. Very stern heavy. Main motor is on a 30" setback bracket. I have a 4-stroke kicker, and both batteries are also situated near the stern.
The motor is a 1995 Johnson 175 hp, carbed. Motor has good compression and is in good tune. Mfr. recommended WOT rpm is 5500.
Old prop was a 17p, 3-blade aluminum in good condition. WOT performance was a top of 37.6 mph @ 5250 rpm.
Goals for the replacement prop were: improved hole-shot (the boat took forever to come out of the water), lower planing speed, maximum mid-range efficiency (we cruise at about 25 mph), and bringing WOT rpm closer to the 5500 mark.
I bought the Titan in a 15p at iboats for about $325. delivered. Dropped 1" of pitch to go from aluminum to stainloess, and another inch to try and raise WOT rpm. finally got to test it this morning. Water conditions and load were virtually identical to those when I recorded performance of the old prop- 2 aboard, approx 45 gals of fuel, usual load of gear. This is my normal cruising configuration. All speed recordings were by GPS. Here we go:
Old prop - WOT = 37.6 mph @ 5250 rpm
New prop - WOT = 39.2 mph @ 5475 rpm
Surprise! I did NOT expect to see a higher top end, but I did and the results were solid- 1.6mph difference, and the tach was just nudging the 5500 mark, right about where I wanted it to be.
Hole shot - MUCH improved. Unfortunately, I didn't have a means of recording it with either prop, but the seat of my pants tells me that I've knocked at least a third off the time it takes to get on plane. It felt pretty impressive.
Minimum planing speed- down from 19-20 mph with the old prop to 16-17 mph with the new. Solid improvement.
1. My speed at idle in forward gear dropped from a little over 3 mph to 2.5 due to the reduced pitch. That's a good thing. I dock in sorta tight quarters (I'm still kinda new at all this) and I was always coming in a little too "hot". If I cut throttle too early, the wind blows me off course. This morning I was able to maintain headway longer and had an easier time of it.
2. The boat tracks much better at no-wake speed. I was always wandering around with the old prop.
All in all, I'm very happy with it. No single improvement was earth-shattering, but every aspect of the boat's attitude and performance showed noticable improvement. Cool beans!
I wish I had the bucks to compare it to a Stiletto Bay Pro II, but the prop I bought does everything I need it to. Can't ask for much more than that.