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Thread: 8L90 100% throttle shifting & WOT shifting

  1. #1
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    8L90 100% throttle shifting & WOT shifting

    Hope you spend nice times.

    Please question:

    In A8 2016-2018 Camaro 8L90 transmission:

    Why In port throttle shifting Point in (100% throttle position) Not match Full throttle shifting points (WOT Shifting)?
    - I’m speaking about the Stock file i did read from the TCM.
    - This situation is in all patterns ( Normal, pattern A, Pattern B and HOT )

    I know always they must match each other, but not in 8L90 as i did see.

    Hope someone explains why they not match!!

    Thank you

  2. #2
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    Quote Originally Posted by Feras D View Post
    Hope you spend nice times.

    Please question:

    In A8 2016-2018 Camaro 8L90 transmission:

    Why In port throttle shifting Point in (100% throttle position) Not match Full throttle shifting points (WOT Shifting)?
    - I?m speaking about the Stock file i did read from the TCM.
    - This situation is in all patterns ( Normal, pattern A, Pattern B and HOT )

    I know always they must match each other, but not in 8L90 as i did see.

    Hope someone explains why they not match!!

    Thank you
    Hope if someone help here, thanks

  3. #3
    Advanced Tuner IARLLC's Avatar
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    GM does that on a lot of cars. This does not seem very logical from the amount that we understand. Their engineers must know what they can and cannot do. The problem is that when we adjust shift speed and/or rpm it is common to mess up the scaling or not understand the lead time needed....then our car won't shift at full throttle. Sometimes we just get these 2 settings too far apart and it messes up. Since we don't know everything that the GM engineers do, it is safest to just set 100% throttle shift to the same number as WOT shift. It seems logical and it reduces the chance that we mess up shifting.

  4. #4
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    Quote Originally Posted by IARLLC View Post
    GM does that on a lot of cars. This does not seem very logical from the amount that we understand. Their engineers must know what they can and cannot do. The problem is that when we adjust shift speed and/or rpm it is common to mess up the scaling or not understand the lead time needed....then our car won't shift at full throttle. Sometimes we just get these 2 settings too far apart and it messes up. Since we don't know everything that the GM engineers do, it is safest to just set 100% throttle shift to the same number as WOT shift. It seems logical and it reduces the chance that we mess up shifting.
    Thank you for the reply