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Thread: AFR control by MAF and VE table combined?

  1. #1
    Lifetime Member 67SS509's Avatar
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    Default AFR control by MAF and VE table combined?

    On a LS1B style pcm what do you log to determine how much of the calculation is coming from the MAF versus the VE table to control AFR? Also does the MAF really control totally after 4000 rpm's? Been wondering about this for a long time.
    2002 Chevy truck, SCSB 2WD, Stroked LS3 w/Big Mutha Thumper cam
    2002SS Camaro LS7/427 with stock suspension setup
    2012 Chevy truck, SCSB 2WD, Magnaflow exhaust + K&N

  2. #2
    Joe (Moderator) joecar's Avatar
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    You can perform an experiment by zeroing out the VE table...

    so if above 4000 rpm the PCM for some reason uses the VE table you will see a drastic change in logged cylinder airmass;


    I talked to some people who said they have seen this in a few situations (possibly the exceptions to the rule).

  3. #3
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    I at one point set that value 400 and later disconnected the maf. The car would start and immediately shut off. Makes sense.

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