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Thread: Throttle position confuddlement

  1. #1
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    Default Throttle position confuddlement

    When should the reported TP be 0%? Mine *never* is... The lowest I've ever seen it was today at 13%. Normally, foot off the pedal is 16-18%. This seems weird to me...
    Hello, my name is Erik and I am a horsepower addict...





  2. #2
    Guess who's back!!!! Black02SS's Avatar
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    You have electronic throttle and probably will never see 0 except when the truck is off.

  3. #3
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    I do have DBW throttle electronics. Seems like such a waste of good bandwidth

    Since I have the commercial version, can't I just tweak the throttle voltages?
    Hello, my name is Erik and I am a horsepower addict...





  4. #4
    Lifetime Member GMPX's Avatar
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    It's normal, ignore it and move on :-)

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

  5. #5
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    Quote Originally Posted by GMPX
    It's normal, ignore it and move on :-)

    Cheers,
    Ross
    Hehe what fun is that :P

    Hello, my name is Erik and I am a horsepower addict...





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    Back from the dead....Does RAFIG tuning still apply to DBW? If so anything worth mentioning? I logged my STIS and LTIT and made the changes based on the average correction at each temp break point. Is this all useless with DBW?

  7. #7
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    Quote Originally Posted by TunasTwins View Post
    Back from the dead....Does RAFIG tuning still apply to DBW? If so anything worth mentioning? I logged my STIS and LTIT and made the changes based on the average correction at each temp break point. Is this all useless with DBW?
    It still applies. The difference is that the idle air is controlled by the throttle blade rather than an IAC valve. For best results, B4349 must also be set according to the throttle size if the throttle has been upgraded to a larger size.

    On my 5.3 idle throttle was something like 7%. IIRC it is around 12% on the 427. These numbers are with 90mm TBs.
    2017 Camaro SS, 2014 Ram 2500 4x4 Cummins 6.7L, 2004 Chevy Avalanche Z71 4̶X̶4̶(now 2WD), 5870lb race weight, 10.93@ 124, Twin TVS1900s, Twin Throttle, 429 LSX, 4L80E, custom 14 bolt rear, V2, R̶o̶a̶d̶R̶u̶n̶n̶e̶r̶(dead), COS3......
    Gettin' the Groceries

  8. #8
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    Quote Originally Posted by DrX View Post
    It still applies. The difference is that the idle air is controlled by the throttle blade rather than an IAC valve. For best results, B4349 must also be set according to the throttle size if the throttle has been upgraded to a larger size.
    On my 5.3 idle throttle was something like 7%. IIRC it is around 12% on the 427. These numbers are with 90mm TBs.
    Is simply reducing the value of B4349 by the TB's surface area diff's in percentage correct ? (ie., changing from a single blade 80mm to twin 58mm)
    Let's assume the factory tune I'm using was for a car with an 80mm TB.
    Surface Area of single blade 80mm = (3.14*40*40) = 5024
    Surface Area of twin blade 58mm = (3.14*29*29)*2 = 5281
    Percentage Diff. is basically a 5% increase in surface area.
    So would you decrease B4349 by 5% to compensate for the 58mm TB ?

  9. #9
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    Quote Originally Posted by twadam View Post
    Is simply reducing the value of B4349 by the TB's surface area diff's in percentage correct ? (ie., changing from a single blade 80mm to twin 58mm)
    Let's assume the factory tune I'm using was for a car with an 80mm TB.
    Surface Area of single blade 80mm = (3.14*40*40) = 5024
    Surface Area of twin blade 58mm = (3.14*29*29)*2 = 5281
    Percentage Diff. is basically a 5% increase in surface area.
    So would you decrease B4349 by 5% to compensate for the 58mm TB ?
    B4349= 100/throttle area
    2017 Camaro SS, 2014 Ram 2500 4x4 Cummins 6.7L, 2004 Chevy Avalanche Z71 4̶X̶4̶(now 2WD), 5870lb race weight, 10.93@ 124, Twin TVS1900s, Twin Throttle, 429 LSX, 4L80E, custom 14 bolt rear, V2, R̶o̶a̶d̶R̶u̶n̶n̶e̶r̶(dead), COS3......
    Gettin' the Groceries

  10. #10
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    Quote Originally Posted by DrX View Post
    B4349= 100/throttle area
    Great! Thanks.

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