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  1. #1

    Unhappy Gutted exhaust and lost 800 rpm

    i gutted the waterbox and removed the resonator, and yesterday when i took the ski out for a test the max rpm was 6500 and mph was 50

    i cut up the hoses used to route the resonator while trying to hook up the free flow so hopefully i have a cheaper option then putting the resonator back in

    the exhaust sounds great, but the ski wont perform.

    anyone have any ideas on how to fix this?

    thanks!

    PS: there are no exhaust leaks or traces of carbon
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  2. #2
    speedskixp's Avatar
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    Quote Originally Posted by chemkexx View Post
    i gutted the waterbox and removed the resonator, and yesterday when i took the ski out for a test the max rpm was 6500 and mph was 50

    i cut up the hoses used to route the resonator while trying to hook up the free flow so hopefully i have a cheaper option then putting the resonator back in

    the exhaust sounds great, but the ski wont perform.

    anyone have any ideas on how to fix this?

    thanks!

    PS: there are no exhaust leaks or traces of carbon
    I dont think it has anything to do with your exhaust . It sounds like your sc crapped out! Pull the intake tube off the front of the sc and see if you can spin the wheel with your finger.

  3. #3
    Gotta love this sport! 05Limited's Avatar
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    I agree. A gutted water box would not have caused an 800 rpm loss. There has to be another issue.

  4. #4
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    Looks like an RXT, but what year...6500 only is a blown clutch SC ..DO NOT fire that thing up again!

  5. #5
    its a 03
    did you guys even look at the pictures? lol

    sorry i forgot to say, its the N/A model


    and it was runing 100% before i started screwing with the exhaust


    thanks again!

  6. #6
    lextoy's Avatar
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    oops, the N/A engines need the tuned backpressure of the stock exhaust for optimum performance. that is my bet.

  7. #7
    Vern's Avatar
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    While screwing with the exhaust, something else was messed up ... the exhaust mods won't hurt, something else is not right ...

  8. #8
    i was under the impression that the majority of the back pressure was from the waterbox and not the resonator

    the gutted waterbox dosent provide enough back pressure?

    and if that is the case, can i somehow add some pressure without having to put the resonator back in?

  9. #9
    Quote Originally Posted by Vern View Post
    While screwing with the exhaust, something else was messed up ... the exhaust mods won't hurt, something else is not right ...

    i dont know what else to check

    throttle opens all the way
    no carbon leaks
    no kinked hose
    no blockages

  10. #10
    Vern's Avatar
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    Phew, thats a tough one ... usually opening up the exhaust on ANYTHING helps performance ... if opening up the exhaust only helped super charged or turbocharged cars, Flowmaster would be so out of business ... my guess would still be an exhaust leak, but if you are 100% certain there is none ... not sure. I have only owned and modded SC'd 4-tecs and two stroke skis, but have opened up the exhaust on a lot of non-blown cars and they all responded well.

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