2005 XB21 ProSport setup and prop?

[buddyjorde]

Just recently bought a 2005 XB21 with a 2.5XS motor. Loving it so far... wondering if anyone has ran a similar setup? The 2.5XS was only built one year, basically a 2.5 optimax 225hp on a 3.0 liter mid and a 3.0 liter sportmaster with 1.87 gears. I’m running a 25 promax prop. For our high elevation (4000’) and an ultrex and fishing tackle that will push her into upper 70s. I’m pretty sure once I get bigger prop and my setup closer, loaded light, correct prop to pad height I may see shallow 80s. Wondering what’s a safe prop to pad height? I’ve read 1/4” below should be plenty safe? Attached a pic of the boat for fun.

 

[RiverRocket]

I had a 225xs on mine when I first got it (2005 XB21 Prosport). My buddy had the 2.5XS on his 2+2 at the same time. Great motor. I see no issues with upper 70's. It will probably do low to mid 80's at your altitude. You should be safe at 1/4" above if you are running around 8" of setback. I ran 3/8" to 1/2" over most of the time with that setback. My boat has always liked the Promax. What RPM are you seeing? That motor can spin up to 6800. I think they said prop for 6400-6800. I would think the 25 would do what you are looking for.

 

[buddyjorde]

I am running about 6200-6400 rpm in the shallow to mid 70s. So I think you’re right, the 25 promax prop is pretty close. It’s got the stock 8” setback, 2” spacer and 6” hydraulic plate. I will (slowly) raise my engine height next time I’m out making passes and see how she likes it. But for now, I won’t go above even or 1/4” above. Thanks for the reply!

 

[RiverRocket]

No problem. Feel free to call if you want. 417-209-4323 Geoff. Great colors BTW.

The opti has a really good tell. If you have 15psi of water pressure in the 60's and 70's you are solid on motor height when you get lower than that you are running high. The R is a different story, it will hold pressure way higher than one should run.

 

[xb03fs]

I think even pitch promax have more lift may want to try 26 also