Torque Management Questions

ebod · May 22, 2003

I see a lot of talk about how the "torque management" system/software affects off-the-line performance on 8.1/Allison trucks.

Excuse my lack of knowledge, but I have a couple of, possibly stupid, questions.

First, is the torque management feature tied to the 8.1L engine, the Allison transmission or the combination of the two? I think that there are Suburbans and Avalanches that come with the 8.1 but not the Allison. Do they still have the torque management system?

Second, are there any good chips/progrmmers that actually defeat the torque management feature?

Finally, how does the torque management feature work? Does it cut air/fuel/spark to the engine until certain RPM are reached? Certain MPH? How big a deal is it in accelerating from slow (but not stopped) to faster or fast (e.g., 5-40, 5-60, 20-60 MPH)?

Thanks for any insight you can provide.

awdvkd · May 22, 2003

I don't know how much help I can be, but my understanding is that from a dead start it is the worst. My understanding is that the computer retardes the timing to keep you from breaking things under open throttle sitsuation. It has been discussed before and if you do a search you will find it. I have heard rumors that a few prgrammers are capable of doing away with it. I have never talked with someone who has actually done it. Hope this helps.

Tucson_02Silverado · May 22, 2003

The basic TQM is suppose to retard the timing, at least with the 4.8/5.3/6.0L. I've notice on my 5.3L that from stop that if you floor it, the TQM will practically kill the engine. What seems to be workaround before having the ECM programmed (The Predator turns off TQM on the 4.8-6.0 version, not sure about the 8.1 version and the Allison) is to find the part throttle that launches the hardest with very little more throttle to second gear then again just a little more throttle. Any more than these definitely boggs the engine down. At the point of part throttle you find that launches hardest, there seems to be very little throttle distance you can add until third gear.

Farmtruc · May 23, 2003

TM pulls timing from your engine when it detects you are abusing the truck. It is worse at wot, but it still exists at part throttle.

Just to give you an example, i enable TM to see what it would really do, I was running 35degs of timing at WOT, and as soon as the trans shifted, my timing was at -4 degs. I was like wtf. Once you start adding mods to your truck it will really poke it's head. I just did two pcms for these guys in san diego, they have minimal mods and they were already noticing it.

if you need more info, shoot me an email, i can do 99-02 gm trucks and ls1's.

thanks,

allen

sierra8.1 · May 23, 2003

I've got the 8.1 and on full throttle starts I noticed that the engine drops off real fast and the allison jumps to 2nd gear pretty quick. what was said about partial throttle starts and gradually feeding it more throttle is about the only way to get this truck to move out smartly(if you wanna call it that!!)

It would be nice to remove the tq mgt. but you would pay for it in tire replacement, but would be a lot more fun to drive(like it isn't now?)

Larry

Rippem · May 24, 2003

I tend to do the "roll out" ..."walk into it" style of driving anyway, and with this driving style the truck works pretty good ! I have been a hot rodder all my life, and even with just 500 miles or so behind the pedal of this thing, I'm quickly getting a "feel" for how to get the most goodness out of it, even with the built in limitations. Without TM I feel that a traction bar of some kind would be needed to avoid axle wrap/hop at low speeds when you nail it!