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Thread: Timing higher than commanded 2001 Vette COS5

  1. #1
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    Default Timing higher than commanded 2001 Vette COS5

    Has anyone ran into timing being higher than the high octane table? All of the timing modifiers have been zeroed out EGR, IAT, etc. Put the car on the dyno had it between 26-28* took it to the track and logged it and saw 37-40*!?!?! Any info would be appreciated!

    Thanks
    2000 RCSB silverado, stock 6.0 transplant, LS6 bumpstick, t76 turbo on meth tuned by me
    best ET 7.02 in the 1/8th

  2. #2
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    How about the PE timing modifier? That'll add timing at WOT. Probably what's happening.
    1998 GMC Sierra K1500 5.7/4L80E, longtubes, 411 w/COS 5, marine cam/intake, Whipple. 91 octane at 6000'.
    1997 GMC Sierra K3500 7.4/4L80E, 411 w/COS 3, Whipple, small cam.
    2004 Corvette Z06 with longtubes.

  3. #3
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    Are you talking about the fuel mixture spark correction (B5908)? It is zeroed out
    2000 RCSB silverado, stock 6.0 transplant, LS6 bumpstick, t76 turbo on meth tuned by me
    best ET 7.02 in the 1/8th

  4. #4
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    That's the animal. I just reread the initial post though and see it's not a couple degrees. Did you log 3D? Those sound like light load cruise timing values. If they're WOT, something is wrong.
    1998 GMC Sierra K1500 5.7/4L80E, longtubes, 411 w/COS 5, marine cam/intake, Whipple. 91 octane at 6000'.
    1997 GMC Sierra K3500 7.4/4L80E, 411 w/COS 3, Whipple, small cam.
    2004 Corvette Z06 with longtubes.

  5. #5
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    Not quite sure what you mean by 3D? It is WOT just seems funny how it seems to change, just curious if maybe the COS5 has something to do with it? It is really weird to see it move that much over the high octane table?
    2000 RCSB silverado, stock 6.0 transplant, LS6 bumpstick, t76 turbo on meth tuned by me
    best ET 7.02 in the 1/8th

  6. #6
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    Man that's an awful lot of timing. Did you put negative values in the boost retard table?
    1998 GMC Sierra K1500 5.7/4L80E, longtubes, 411 w/COS 5, marine cam/intake, Whipple. 91 octane at 6000'.
    1997 GMC Sierra K3500 7.4/4L80E, 411 w/COS 3, Whipple, small cam.
    2004 Corvette Z06 with longtubes.

  7. #7
    Joe (Moderator) joecar's Avatar
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    Post log/tune files.

  8. #8
    Joe (Moderator) joecar's Avatar
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    Other than timing being wrong, does PCM execute everything else ok...?

  9. #9
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    Quote Originally Posted by joecar View Post
    Other than timing being wrong, does PCM execute everything else ok...?
    Thank you all appreciate the posts but we actually just caught it. We had 100% in the octane scaler but was actually out of limits. Saved at 99% and had to resave it back to 100% and was no longer out of limits. Rookie mistake good lesson

    Sent from my SM-G930V using Tapatalk
    2000 RCSB silverado, stock 6.0 transplant, LS6 bumpstick, t76 turbo on meth tuned by me
    best ET 7.02 in the 1/8th

  10. #10
    Joe (Moderator) joecar's Avatar
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    So it's good now...?


    Note for other people reading this thread:
    when you open a tune, go View->Show Calibration Window, and goto the Out of Range tab, if you see any tables mentioned here you should fix each one;
    when you go to those tables, you will see the out of range cells marked with either blue dogear corners or with a red box around the cell;
    you fix all the OoR cells by doing this:
    - edit the OoR cell to either max-1 or min+1,
    - do this for all the OoR cells,
    - save tune,
    - exit tunetool,
    - reopen tunetool
    - set each of those cells to max or min as appropriate,
    - save tune
    (this is a special trick required due to tunetool only saves changes it detects, and setting an OoR cell to min/max is not detected).

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