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  1. #1

    Just how much Boost can the cast pistons handle safely?

    How much boost can these stock cast pistons handle safely in the GTX SC models?

    Also has anyone with a GTX SC installed a set of Rotax overdrive gears for the SC?...Thanks...PR...


  2. #2
    Red Devil's Avatar
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    Well, I ran all last summer over 8 and made a couple of runs at 11 this year and no problems yet. I don't plan on doing this but a few more times though before the internals are done. I have always made sure to stay off the limiter and now have 55 lb injectors with Nils' fuel controller to prevent me from running lean, which we all now is our motors worst nightmare. If anything, I will be running rich at this point.

  3. #3
    Red Devil, thanks for the input, I know in the auto flields a safe zone is no more than 6 psi with hypereutectic or cast inerst...PR...

  4. #4
    Been there and back! BDNJ's Avatar
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    PR: I'm running 12.4lbs on stock pistons, but, like RD, have some safeguards: Les' fuel controller/pump to keep a/f safe.

    -Brendan
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  5. #5
    Moderator Franko's Avatar
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    Nice boost Brenden. What speeds are you seeing these days?

  6. #6
    Been there and back! BDNJ's Avatar
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    Quote Originally Posted by Franko
    Nice boost Brenden. What speeds are you seeing these days?
    Franko: The last time I rode I ran 78.3 with only 11 lbs and the 3 blade skat. This wknd I will be running the boost you see here, plus my newly repitched 4 blade solas. Picked up the boost on Les' recommendation of going with a 4" intake.

  7. #7
    Moderator Franko's Avatar
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    Duh, I could have looked at your sig about your speeds Let's hope the new prop yields more than 1.7 mph. Sure would be cool to be able to advertise speeds starting with an 8.

  8. #8
    Been there and back! BDNJ's Avatar
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    I'm thinking it's going to be real close. Might need Shibs to drive down and run it to put me over the top! Pushin' 225!

  9. #9
    Jarrett's Avatar
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    Brenden, great numbers. Are you coming to MB2 this year? If so, hope to meet you.

    Also, would you mind talking about your new intake setup on this thread?

    http://www.greenhulk.net/forum/viewt...?p=56025#56025

  10. #10
    Been there and back! BDNJ's Avatar
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    Quote Originally Posted by Jarrett
    Brenden, great numbers. Are you coming to MB2 this year? If so, hope to meet you.

    Also, would you mind talking about your new intake setup on this thread?

    http://www.greenhulk.net/forum/viewt...?p=56025#56025
    Jarrett: Oh I'll be there alright. Looking forward to meeting you and everybody down there. Long , long drive - hope we have some good weather.

    I will add to the other thread soon. Thx.

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