What can I do??

[white03]

I just put a 280 (consumer version...not OS or ROS) on my XB2003 and I have tried 2 props:

Chopper II in 30 pitch with a Jaco's cut by JC - 68-6900 RPMs max at 89 MPH.

Trophy Plus in 26 pitch - 7400 RPMs at 88 MPH

I think the Trophy is hitting the rev limiter right?? Isn't the limiter around 7400 on a consumer 280?? This calculates to 8% slip wich is a little high maybe, but in the acceptable ballpark...right??

What can I do to get to the mid 90's??? (and I don't want to put 260 electronics on it or remove the rev limiter)

Shouldn't my 280 pull the Chopper II to 7400 RPMs? I read where others are pulling 30 pitch Choppers on their 280's and getting speeds in the high 90's...what's wrong with my 280 that it will not pull my chopper to the rev limiter??

\Help please...I'm cornfused :?

Bill

 

[TBuck2003]

280 on 03

Bill,
30p chopper or anything for that matter on a recreational 03 with 280 is way to much prop.Just because you have a 280 dos not mean it will pull lots of pitch.Your motor does not even start to come alive (power band) until over about 7000-7200.Too much pitch will increase your slip and lug the motor down to the point you will not be receiving your full power.Proof positive 4" less pitch on your trophy only ran 1mph slower than your 30 chopper.Why? because trophy was in power band chopper was not.Your rev limiter if it is stock will be at 7750 rpms,so if your only getting 7400 out of trophy you are not there yet.Where is your motor height? On that rigs combo you should be 1/4 " below pad (make sure this is accurate) and be able to pull some more revs out of the 26 pitch trophy.I have a feeling your motor height is too low and is not allowing the rpms to get you into making some real 280 power.Depending on load(everybodys definition is different) you should be able to pull between a 26-28 pitch over hub three blade to see speeds into the nineties.For example 27p @ 7750 with a conservative 10% slip would be 95.36 mph assuming it is a 1:87 gear ratin the other hand your trophy at the rev limiter 26p @ 7750 with 8% slip(four blade) should be at 93.87 mph.Obviously these are rough estimates but will definately get you real close to being in the ballpark.If you have any questions call me at 330-425-3629.Thx

Todd

 

[white03]

Todd,

Thank you for the reply, you confirmed what I thought about the ChopperII..basically it is to much prop and lugging the motor down. I really wanted to run this 30, it is a beautiful prop and in brand new condition, but if it is too much then that's that.

Not sure what my motor height is, I'll have to measure it...but I can tell you I have the typical 14" setback, the jackplate is as high as it can get on the set-back plate and the jackplate is as high as it will move to. In other words if I need to get higher to get 1/4 inch below the pad I will have to raise the set-back plate on the transom to get there.

I have read and you confirmed that the 280 powerband is in the 7000+ rpm range, which is why I want to get my rpms up.

Stange thing with the Trophy is the more the trim and RPMs went up, the higher the bow went in the air. Got to the point at 7400 rpms that I was afraid to trim it up any more because the bow keep going higher. I have always read "flat is fast" and I am now wondering if the Trophy has too much bow lift to be efective above 7000 rpms? If I trim down the bow comes down, but so do the RPMs.

I think I can get my hands on a 28 RE4 to try, not sure if I can find a 26-28 three blade over the hub.

Any other comments or suggestions will be greatly appreciated guys..I want this baby to RUN !!!!

Thank you

Bill

 

[TBuck2003]

280 03

Bill,
Part of the problem may still be that the motor is to low,when the motor is moved up you will lose leverage (bow lift) and boat will run flatter.Still being new to the boat an Allison will be weird to feel because of the hull lifting out of the water,with that being said you do not want bow to be sky high this can actually scrub off speed.Your ultimate goal is to be as close to neutral trim as possible and have the boat be lifted evenly off the water.Hope this helps and good luck and be safe.You only want to run props that are going to maximize rpms this will help performance numbers and be easier to drive at speed.Later


Todd

 

[Bob Ant]

Bill,
I have the same boat with a consumer 280. My motor is 1/4 below pad with 14 inches of set-back. I normally run a 28 ET in the high 90's. I tried a 30 Ally cut chopper and returned it as it did not perform as good as the ET . My speeds fully loaded with 3 batteries,on-board charger and a bunch of fishing gear are normally in the 97 to 98 range. YOu definaltely should see more top end. I f you would like we could meet at Guntersville and you could try my props, glad to help out any way I could. I have a nice assortment of paperweights.(props)

Best advise is probably do whatever Todd recomends.

Bob A.

 

[ALLISONMAN]

bill ya need ya a 28et for your topend stuff and say around a 26 drag4 for fishing and running loaded!!!! and like todd said sounds like your engine height is a bit low even to about 1/4" below and be carefull some 2003's have a lot of lip and sometimes it will want to blow out with ya around 100mph!!! if you feel the nose drop and back pick-up ease out of the gas and get slowed down and thenyou will probably have to have some of the lip worked on!! hope this helps ya

 

[GotMyAlly]

If you're having to trim that much to get your RPMs up, it sounds to me like your motor is too low. I'd try raising it a little. I'd rather run the motor a little higher with a little less trim in most cases. I would think the 30" would be okay with a light load but if you are carrying a heavy load you may have to back off the pitch. You should definitely be getting more speed than what you are.....my 225 runs faster than that. If you decide to part with the 30" chopper, I may be interested in buying it off of you if it is a flo torq prop.

 

[BigRedAlli]

Bill, have to agree with the rest about your motor height.i can turn a 28p Ally cut 7500-7600 on a good day with a 260.should be easeier with a 280.
Like A-Man said, the Drag IV's run nice on the 03's,I also like the Ally cut choppers,which can be tuned to your like'in.
Be carefull fly'in to high.On a 2003.With the pad level to the ground, the nose is actually pointed down quite a bit.Which is why they run so good flat.

Todd, I seen a prop on Bob Ant's boat this past weekend that looked really interesting.What's it called? I didn't know you all had over hub props

 

[TBuck2003]

Big Red Alli

Hey Marty,
How are ya man? Things cool here.That was a T-3x Sport on Bobs ride.14.5 " x 28.Good running wheel on the 03s,even the Grandsport.Same wheel I run.Tom ran one that was about 3mph faster than any he had tried on the SS with the 200.We make alot of over hub props just not a huge market for that stuff right now.Gotta stick with the bread and butter.Next time we hook up we will bolt one on,and give her a rip.Tell your better half I said hello and I miss her razzin me from dawn till dusk!!!! Later Bud.

Todd