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  1. #1
    imp0ster's Avatar
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    Max Safe Timing for X-SC @ Sea Level around 8200RPMs

    still seeing about 8.5psi even though my final slip came to 152 in/lbs but I want to get the revs up to see what I can get from the SC before dumping in the ET wheel.

    Anyone know about the area where KR kicks in at 101kPa past 8K RPMs? I don't have a way of data logging but I have my AFRs dead nuts accurate from the MAP Editor.


  2. #2
    GRF + DashPac:) seadoo02xp's Avatar
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    101kpa? That's basically atmosphere pressure. Do you mean 201? That would be 14# or so. With an x wheel on my boat at 8400-8500 I am seeing 177kpa and my timing is at 38. If you don't have knock control I wouldn't go that high. Nils told me I'm on the edge where I am at. I am And 700above sea level. Not sure how to factor that in either.

  3. #3
    imp0ster's Avatar
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    yes sea level +38 700 up eh? Air lower is denser = more power. I think I'll try adding percentages to the 8k+ area until it sneaks up to about 33 or 34 and see what I get. That should be a good starting point for me if you have no issues. Thanks for the reply!

  4. #4
    GRF + DashPac:) seadoo02xp's Avatar
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    I was running 34 degrees at 20psi (240kpa ) on a turbo setup and had no high rpm knock. You should be fine with a x charger

  5. #5
    imp0ster's Avatar
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    psi for psi a turbo is way more efficient. Less heat too. Wish I had a stand alone KR sensing box like the MSD KR alert that I could mount somewhere visible.

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