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Thread: Light Throttle Knock Retard

  1. #1
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    Default Light Throttle Knock Retard

    I have been getting light throttle KR usually upon tip-in around 2000-2500RPM. I cant seem to shake this off. Please advise on what can be done. Ive removed burst knock and runing 10lbs boost. WOT is OK.


    SOS!
    2002 GMC Sierra ECSB
    Turbonetics T7675 6lbs boost, 42lb injectors, Single 4 inch exhaust with Hi-Flow Cats, 6.0 swap, Comp Cam LS9 Cam, EFIlive Tune, E-fans, Snow Performance Meth Kit, soon to add KB Boost a Pump,

  2. #2
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    Default Re: Light Throttle Knock Retard

    Quote Originally Posted by jamesbond2509
    I have been getting light throttle KR usually upon tip-in around 2000-2500RPM. I cant seem to shake this off. Please advise on what can be done. Ive removed burst knock and runing 10lbs boost. WOT is OK.


    SOS!
    I think that might be a side effect of their attempt to maximize the gas mileage, my 2000 Z28 does the same thing. On cruise at 70 it's fine, but hit a bit of grade and suddenly knock retard. Sometimes you can hear it. I've always assumed it's too much advance for the local 91.

    Ira

  3. #3
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    What are the timing and manifold pressure figures at that point?

    2 ways to remove knock. Take away timing or add fuel or both.
    Personally I dont think manipulating the KR system so its less sensitive to knock is the right way to do things.
    \"You Can Never Have Enough Horsepower\"

  4. #4
    Lifetime Member GMPX's Avatar
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    Quote Originally Posted by caver
    Personally I dont think manipulating the KR system so its less sensitive to knock is the right way to do things.
    Agree, in fact you can see some GM engineers (Holden) went to some lengths to tune the knock sensitity per cylinder.

    Cheers,
    Ross
    I no longer monitor the forum, please either post your question or create a support ticket.

  5. #5
    Joe (Moderator) joecar's Avatar
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    Drive around logging KR, RPM, MAP and then use the histogram/map to guide you in altering the spark table.

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