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Thread: What am I doing wrong here? I have really harsh defueling!

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    Default What am I doing wrong here? I have really harsh defueling!

    Cant figure it out why its defueling really hard and coming in again so hard once it shifts all help is greatly appreciated!
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    Lifetime Member THEFERMANATOR's Avatar
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    B0741, B1102, and bring your timing tables back to reasoneable levels at part throttle. ANY and I do mean ANY sharp, jaged, spikey points in either B0741 or B1102 WILL make it shift AWFUL, NASTY defuels, and WILL WRECK clutches in your ALLISON. Keep B0741 so that it will just allow 100 at the very top portion, just basically carry the factory curve on up through the last 2 lines instead of it going flat. Then go into B1102, and only allow it to be able to reach peak torque at the very top, but you MUST maintain the factory curve/arch to the table. I've spent to many hours to mention trying to get mine to reach full fueling(max torque), and to try and minimize that surge during defuel. Many just leave it so that it peaks out at 90, and work within those limitations. You're going to have some time ahead of you to get them ironed out. If you put them back to stock though, I guarantee you it will stop. Just go slow with your changes, and keep them smooth.
    1995 GMC 2500 SUBURBAN powered by 01 DURAMAX/ALLISON, little of this, a little of that,
    DIAMONDEYE 4" exhaust, CORSA muffler, AFE stage 1 dry filter, custom tuning by me, KENNEDY single pump and pump rub kit.

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    Quote Originally Posted by Diesel Doctor of Tn View Post
    Cant figure it out why its defueling really hard and coming in again so hard once it shifts all help is greatly appreciated!
    Is it defueling on part throttle shifts or at wot? Looks to me like it should be adding fuel in your part throttle shifts...

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    Thanks a bunch! I'm going to work on it and will let you know.

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    At wot its defueling.

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