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  1. #1
    icdoo's Avatar
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    Thumbs down Mods but no speed gain

    Just picked this ski up and have been chasing missing speed since. 04 rxp with s3 wheel, 42s, 3" riva front air, thru hull with shorty box and new type 3 cooler to replace leaking/blocked gen 1., 15/20 prop and ss ring with good clearance. This thing barely hangs with my stock 04 with wedge and grate running 67-68. Good compression in all 3 holes, 10 lbs boost, 8100 rpm. What am I missing? Did notice pto plug was a little darker than the rest. Sound like a higher rpm fuel delivery problem? Any help from you all would be appreciated. Tired of talking this boat up and someone on my stocker keeping up


  2. #2
    Mothman's Avatar
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    You're running 8100 on a 15/20? If the wear ring and impeller are good... What is the nozzle diameter? They may have gone with a larger one.
    Also, what are your afr's?

    **Did they de-pitch the 15/20 and not tell you??

  3. #3
    Vern's Avatar
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    Setup sounds good, and if you are pulling the 15/20 to 8100 rpms I think the motor is fine. I would look very closely at your intake grate, pump shoe, ride plate. You should be running 75 mph if everything is optimal. Is the 15/20 a Solas 4 blade?

  4. #4
    icdoo's Avatar
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    I was told a 15/20 with some pitch work. It is a four blade. Stock nozzle. Have no way to measure afr's yet, on the list. Vern, would those areas scrub that much speed? we're talking 7- 8 mph. I know the ride plate holes are filled. Bottom of ski is a litle rough too. Did notice water box gets a little warm, got really hot with gen 1 cooler. Could sensor be adjusting for the higher egt's. I will pull the pump now to check prop

  5. #5
    icdoo's Avatar
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    15/20r. Slight pitting on trailing edge, seal wasnt perfect. Gonna try new seal. Do have a 15/19 three blade that came with it. Looks like he tried it with no luck. Anybody getting good results with this prop?

  6. #6
    icdoo's Avatar
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    Vern..shoe, grate, and plate look like they all flow together nice and sealed nicely. Anything else I should be looking at there?

  7. #7
    DaveC's Avatar
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    So the plate and intake grate have a smooth transition ? Nothing there that you can hang a finger nail on because it sticks down further ? Which intake grate is on it ?

  8. #8
    icdoo's Avatar
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    Stock grate. Looking at this one next to stock ski with worx grate, stock one does hang a little lower than rideplate. I will address this issue next. Between that and the seal, should help. Maybe just give the learning key to the guy riding stocker, then I will fly by... Any input on the three blade? jc..

  9. #9
    DaveC's Avatar
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    The four blades are almost always faster. The 15/20r, have you had it out to make sure the blades appear about the same, that is one blade obviously dinged or pitched differnt ?

    The Riva grate is usually the fastest as long as you ride fairly smooth lakes, river etc.

  10. #10
    Mothman's Avatar
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    Maybe you have a slight cavitation issue at speed. What are the hours on this craft? Has the carbon seal been changed?

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