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  1. #1
    RHeller1's Avatar
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    power valves open

    has anyone played around to see if there is performance to be had by opening the power valves earlier?


  2. #2
    Moderator OsideBill's Avatar
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    On the 1200R ski you could adjust with the advent to open at different RPM's, Pro-Tec made a controller for the PV's not sure if it will work with the 1300 EFI's, it spliced in just ahead of the PV motor.
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  3. #3
    RHeller1's Avatar
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    So are people getting better performance from opening the power valves earlier or later?

  4. #4
    Moderator OsideBill's Avatar
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    I never really stuck with the servo motor set-up long enough to determine. The principle is to make your exhaust opening smaller for bottom end torque, then open for top end peak flow. So as far as performance gains from altering, it is more of a midrange transition thing. I run the gas valves and they transition through out the range, much less noticeable then the servo.

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