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  1. #1
    ncdoo's Avatar
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    CP 9.5 Pump Gas?

    Thinking about going with the CP 9.5 pistons on my rebuild. Can you run pump gas safely with these? Any other mods required when bumping up the compression?


  2. #2
    Eastside Powersports Slow 91's Avatar
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    yes. I run these in my RXTX with a 68-140 @ 9k on 93 octane and I run Wiseco 10:1 in my rxp with a 137 +4 @ 8800 93 octane

  3. #3
    imp0ster's Avatar
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    Yes. You need a tuner to add a bit more fuel to compensate for the bit more heat

  4. #4
    boost junkie skidoochris's Avatar
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    the SC on these skis do not make much boost in the lower rpms where knock is a problem with a turbo
    pump gas is good to about 15psi with the correct tune with the higher than stock compression

  5. #5
    I have a full set of stock compression CPs for sale...I believe they're .020 over. I bought them through Snoman over the summer.
    They're brand new in the box...decided not to use them afterall. Changed my mind about hanging onto them for a rainy day.

    Sean

  6. #6
    rxpredviper's Avatar
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    Quote Originally Posted by Slow 91 View Post
    yes. I run these in my RXTX with a 68-140 @ 9k on 93 octane and I run Wiseco 10:1 in my rxp with a 137 +4 @ 8800 93 octane
    wow is your knock sensor turn of?? if not you loosing 2 mph .. and go wot and turn off motor and check with fine loop you will fine aluminum in your spark plug for sure ..if you continue that way put some ceramic coating on piston..

  7. #7
    imp0ster's Avatar
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    Here that Chris!?!?!? lol

  8. #8
    Eastside Powersports Slow 91's Avatar
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    Quote Originally Posted by rxpredviper View Post
    Quote Originally Posted by Slow 91 View Post
    yes. I run these in my RXTX with a 68-140 @ 9k on 93 octane and I run Wiseco 10:1 in my rxp with a 137 +4 @ 8800 93 octane
    wow is your knock sensor turn of?? if not you loosing 2 mph .. and go wot and turn off motor and check with fine loop you will fine aluminum in your spark plug for sure ..if you continue that way put some ceramic coating on piston..
    WHAT?

  9. #9
    dpracing's Avatar
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    Quote Originally Posted by Slow 91 View Post
    Quote Originally Posted by rxpredviper View Post
    Quote Originally Posted by Slow 91 View Post
    yes. I run these in my RXTX with a 68-140 @ 9k on 93 octane and I run Wiseco 10:1 in my rxp with a 137 +4 @ 8800 93 octane
    wow is your knock sensor turn of?? if not you loosing 2 mph .. and go wot and turn off motor and check with fine loop you will fine aluminum in your spark plug for sure ..if you continue that way put some ceramic coating on piston..
    WHAT?
    I think he's saying it will detonate and destroy the Pistons. That's why he's talking about aluminum on the spark plugs. That's my guess......

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