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  1. #1
    skigolfnut's Avatar
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    Prop set back and repitch questions

    I wanted to see the pros and cons of the prop set back and re-pitch?
    this is for Closed Course racing, and hole shot is a must,
    Does the set back and adjustment just help hook up and top speed? does it also help hole shot?
    what about taking off the nozecone?
    Last edited by skigolfnut; 12-14-2012 at 09:57 PM.


  2. #2
    R88ory RXP's Avatar
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    2 of my props are set back, helped clean up a little cavitation on my RXP that we use on the weekends but thats only got air intake/exhaust mods with a x charger, I tryed the set back on my lightwieght RXP and it was good but It didnt seem to help and cavi may have even been slightly worse....

    I think with the bigger power running the set back had removed too much water volume from between the prop and stator

    Bear in mind on the lightwieght I have a bearing seal on the d shaft and a seadoo centre cone in the pump also so there are some wuite big differences that could have a massive effect.

    I think that you are at a point now where testing different setups is the only way you will find whats good for you, your boat and CC racing.

  3. #3
    skigolfnut's Avatar
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    thanks, I am running the et-137 wheel, with the rotax racing ECU and I know I move a lot of water--the bearing seal on my driveshaft really helped the cavitation issues off the line,
    One of the members said that having the larger venturi 85/86 mm makes the cavitation worse, and that I should put on the 83/84mm ring and tune my current prop to 8550, then when summer hits put the 84/85 ring back in,

  4. #4
    R88ory RXP's Avatar
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    Quote Originally Posted by skigolfnut View Post
    thanks, I am running the et-137 wheel, with the rotax racing ECU and I know I move a lot of water--the bearing seal on my driveshaft really helped the cavitation issues off the line,
    One of the members said that having the larger venturi 85/86 mm makes the cavitation worse, and that I should put on the 83/84mm ring and tune my current prop to 8550, then when summer hits put the 84/85 ring back in,
    This is true. Thats where the adjustable pump cone comes in, it pushes the pressure back up in the ventury with the larger ventury fitted, i would highly recomend the pump cone from les. Also helps get things spot on when going from salt to fresh water..... you will see differences and a small change on the cone gets it spot on.

    R88

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