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Discussion Starter #1
I didn't search for the answer, but can someone (or several members) explain what torque management is? I've read that the CTS-V and the C6 Z06 both suffer from this and yet I can't understand how this comes into play with a stick shift and a 4,000 rpm clutch drop or on a dyno graph in 4th or 5th gear...

Also, how does torque management save / preserve the drive train when the engine RPM is high enough to make peak power numbers?
 

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CaddyGeek said:
I didn't search for the answer, but can someone (or several members) explain what torque management is? I've read that the CTS-V and the C6 Z06 both suffer from this and yet I can't understand how this comes into play with a stick shift and a 4,000 rpm clutch drop or on a dyno graph in 4th or 5th gear...

Also, how does torque management save / preserve the drive train when the engine RPM is high enough to make peak power numbers?
Good question...I wonder the same thing!!!
 

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As far as I know, torque management is just a function of the traction control system (TCS).
If the rear wheels start to break traction, the EBCM (Brake control module) sends a signal to the PCM to tell it to reduce engine torque output in order to regain traction. When the PCM sees this signal it reduces torque by retarding ignition timing, and turning off selected fuel injectors.
If it still can't regain traction it will begin applying the brakes.
There is typically a two wire setup going between each module. One wire tells the PCM what the "requested torque" is and the other coming back from the PCM tells the EBCM what the "delivered torque" is.
Looking at the schematics I see that the CTS-V is set up in exactly this fashion.

Hope that answers your question.
 

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ewill3rd hit it on the nail. T. M. is used to reduce the engine output for a predetermined amount of time until the issue, it being traction, miss-fire, or on an auto, in-between shifts. It hurts the performance because the engine is being told to produce less torque to induce less wheel spin or most likely, it was introduced to eliminate the amount of strain the driveline will recieve at any or specific situations like "zero to sixty in under 5 sec shananagans!!!"

Though the motor is capable of generating 400hp/395tq., it will fall under that in order to save itself, well in a way since it was programed for this.


The amount of TM can be viewed and disabled with a tuning software of your choice. But it should be done with care and knowledge of the available parameters for if done aimlessly, you'll end-up with a limping engine and it wont be covered under warranty!!! There are a few programs ls1edit, hptuners (i own this one for my Z28 with a 408 stroker), efilive, and a few others.
 

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When Traction is turned off the torque management feature should be disabled. It's just a software function of the traction control system.
 

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Discussion Starter #7
ewill,

Thanks for the reply. Sounds ok to me...

I bumped this to get a few more people to chime in because I recall TM being a question asked by one of the tuners (stealth?)... as in do you want to disable TM? If TM not an issue with TC turned all the way off, then it doesn't completely make sense why you would want to disable it. Must be murder on the brake pad life in the rain / wet weather with the TC left on because the computer can't retard the engine timing.

Am I off base guys?
 

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ewill3rd said:
When Traction is turned off the torque management feature
should be disabled.
I've heard this rumor--can anyone confirm?
 

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First here is a quote from description and operation out of the service manual.

When drive wheel slip is noted while the brake is not applied, the EBCM will enter traction control mode.

First, the EBCM requests the ECM to reduce the amount of torque to the drive wheels via the requested torque signal circuit. The ECM reduces torque to the drive wheels by retarding spark timing and turning off fuel injectors. The ECM reports the amount torque delivered to the drive wheels via the delivered torque signal circuit.

If the engine torque reduction does not eliminate drive wheel slip, the EBCM will actively apply the drive wheel brakes. During traction control braking, hydraulic pressure in each drive wheel circuit is controlled to prevent the drive wheels from slipping. The master cylinder isolation valve closes in order to isolate the master cylinder from the rest of the hydraulic system. The prime valve then opens in order to allow the pump to accumulate brake fluid in order to build hydraulic pressure for braking. The drive wheel inlet and outlet solenoid valves then open and close in order to perform the following functions:

Pressure hold
Pressure increase
Pressure decrease
 

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I am trying to think of the best place to look for a difinitive answer on the torque management thing.

I know automatic transmissions use TM to control shift points also, but on a stick it shouldn't matter.
 

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ewill3rd said:
I am trying to think of the best place to look for a difinitive answer on the torque management thing.
I know automatic transmissions use TM to control shift points also, but on a stick it shouldn't matter.
I'm surprised StealthV hasn't chimed in as he knows the answer! :D
 

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I've asked this question more than a few times, and heard plausible stories, but NO FACTS. The tuners I have asked have talked about reducing it for good effect, but still NO FACTS.
 

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With tc off Torque management is still on!!!!!!!!!
:banghead:
It makes a big difference when the tuner disables or lessens torque management:D
 

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Rick's on a business trip; you may not hear from him until November 21.
 

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Supposedly my 03 Silverado with 5.3 has Torque management as well, but ain't got no T/C. I think it is just the computer limiting torque at certain times (aka choking back the motor when you want it most...). Another ECM tuner who sells his stuff on www.gm-trucks.com turns off TM for LS powered trucks along with other adjustments of course...
 

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Sorry for the delay; the wireless interent here at the hotel has been extremely flakey all week.

Without having the tuning software handy, the best I can remember is the V is torque limited to something like 340 ft-lbs of calculated engine output. This value can be raised independent of the traction control system.

For Silverados (or any other Gen III V8 with a slushbox), removing TM really wakes up the vehicle; my Silverado SS is slightly more violent than stock. :lildevil:

After this week's trip in the States is over, I'm off to Italy for a week. Wonder what rental car I'll get from Europcar? At least I did reserve one with a stick but will probably be some anemic POS. God bless America and push-rod V8s. :)
 

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Without having the tuning software handy, the best I can remember is the V is torque limited to something like 340 ft-lbs of calculated engine output. This value can be raised independent of the traction control system.

For Silverados (or any other Gen III V8 with a slushbox), removing TM really wakes up the vehicle; my Silverado SS is slightly more violent than stock. :lildevil:
Sorry to revive an old thread, but I need to ask a couple of questions.

1. How easy is it to edit the specfied torque using a programmer? Can you use a programmer such as the predator or ls1edit to change the torque figure?

2. Can the differential in the 2004 CTS-V handle 395 ft-lbs of torque?

Thanks!
 
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