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  1. #1

    Boring Out Venturi to Regain RPM's?

    What do you guys think of boring out the venturi to regain lost rpm's due to heat? Will I be able to get back revs and a little speed? I don't expect it to be as fast as before but at least get my revs up tp 7900 coz I am only at 7600-7700 right now. Thanks!

    John


  2. #2
    Site Admin Green Hulk's Avatar
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    I wouldn't advise it. You should look into repitching your impeller.

  3. #3
    rx4pain's Avatar
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    I was going to post something about this...over on SD.net I read someone with a PPG Level II kit (RR ECU and IC basically) bored their venturi nozzle to 84mm and he said he actually increased his acceleration and his top speeds were something like 74 to 76 with full and low fuel in high temp weather...is this for real?

  4. #4
    GRF + DashPac:) seadoo02xp's Avatar
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    yes sir it is for real, i guess i could take a picture of my gps but i didnt, but the thing with my setup is.....ppg pitched my prop too tall on teh top end but for some reason i still had killer acceleration but it just couldnt pull past 8100 rpm, so i bored it out about 2 mm added a riva intake and my r's were right up there where i needed them and i was hitting teh speeds i posted, i wouldnt recommend it on a stock ski though, i have everything hulk had before he ported his head, so i guess you could call it a level 2, but it is no bullshit, it worked for me, i have a small amount of prop spin at takeoff if i nail it from idle, possibly the pitch or nozzle is causing this, i have a ss wear ring and the impeller is in perfect shape, so who knows but if i just barely off idle punch it it hooks up perfect,

  5. #5
    RXPDAVID's Avatar
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    Seadoo02xp, Did you bore the steering nozzle also? If so how much?

  6. #6
    GRF + DashPac:) seadoo02xp's Avatar
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    no i didnt touch the steering at all,

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    Jarrett's Avatar
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    seadoo02xp, great numbers. I'd love to see a video of another RXP hitting 76+ MPH. Think you can hook that up? I bet Hulk would host it for you. What do you say?

  8. #8
    I've been tempted to send my venturi to skat-trak to have them bore it out to install the interchangable rings.

    I love the top speed, but I would gladly trade 1-3mph for acceleration.

  9. #9
    GRF + DashPac:) seadoo02xp's Avatar
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    well i would if i had a video camera, i guess we will just have to imagine it, haha, i guess i could take a pic of my gps thats the best i can do

  10. #10
    Jarrett's Avatar
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    Quote Originally Posted by seadoo02xp
    well i would if i had a video camera, i guess we will just have to imagine it, haha, i guess i could take a pic of my gps thats the best i can do
    Ah bummer, guess we will just have to put on our fantasy caps for that one...

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