I have seen this mentioned in some Posts, but have no idea what this is or how it works. In the posts that I have seen, the advice has been to turn this system off, why? I just installed a 3.42 gear & a SY3500 Yank T-C. I also used the LS1 Edit to program the 3.42 gear. Do I need to turn my torque management system off? Also should I increase my fuel cut off from 6200 RPM'S. If so how high? This car is a street only, no drag strips. Thanks. :cheers:


[Modified by clancy, 1:47 PM 2/22/2003]


[Modified by clancy, 2:57 PM 2/22/2003]

 

Turn it off

 

WHY???? :confused: What does it do? How will it change the performance of the car? :confused:

 

Without going into alot of technical talk here..simply put, the engineers at Chevrolet tried to please the majority of the ultimate end users of the Corvette with a smooth but performance oriented shift pattern. A shift that would not offend the older more mature driver who has a taste for performance but still requires a manageable driving sports car. On the other hand they also wanted to accomodate the younger more enthusastic driver who truly enjoys a performance feel in the car. Therefore ...TMS..or Torque Management System. This is a electronic program that has been set up in the PCM to delay for a split second the rpms in the shift pattern so that the end result is a smooth shift. Once removed by outside PCM programs you are now left with the freedom to program when your car shifts and by increasing the line pressure actually give the shift more quickness and surety between shifts. There is a limit to how much pressure the program can adjust electronically ( I believe max is 89 lbs.) ...BUT..Many of us gearheads and true enthusiasts require even more of a kick between gears and want absolute immediate shifts and control when we shift as if we were driving a manual transmission ( that's me for one)..next step is to install a Transgo shift kit!! This little gem..this secret best bang for the buck mod has been around for 35 years and is a real favorite of serious drag racers and enthusiasts that just won't settle for the engineers idea of a performance shift. If you have never driven a car with a modified valve body including the Transgo shift kit you just don't know what your missing..Once you do...your hooked!!:eek:

I hope this is a sufficient reply..I hope this helps..:D

More about Transgo shift kit here..http://www.txchange.com/transgo.htm

 

It also retards timing on hard accell thats a bad thing

 

Thanks Vstella, had I read your answer first I wouldn't have spent two hours finding GM's explanation of TMS. For the curious, this is what GM says.
Torque management system helps protect the powertrain by reducing the amount of energy & heat generated by frequent severe shifts that can occur when a vehicle is stuck in a snow bank or similar situation & must be "ROCKED" Again thanks Vstella,I'm going to turn off my TMS, firm up my shift points, & see what happens. If I'm still not :) the next step will be the Trans Go shift kit. :cheers:

 

So does the LS1 Edit, Predator or Hypertech turn off the torque management? :confused:

 

LS! Edit and predator do have the capabilities to override the TMS..:D I don't believe that the Hypertech does..But I am not sure about that.

 

Vince - Thanks for the clear concise description of TMS. I've got LS1 Edit coming soon and wanted some info other than the popular cry "turn it off". If you've got the time or want to send me a private email, can you give me the full technical talk version?


[Modified by mfrnka, 11:37 PM 2/22/2003]

 

I have another view... I think they added it to save money. With the spark retarded and torque reduced they save on warranty rebuilds. These 4l60's are at the upper limit of what they can take with the plastic actuator pistons and all. Drag race anything over 400 horses and you'll be rebuilding in a year or two. Just a thought... :crazy:

MikeV

 

Altering TM function via LS1Edit appears to also disable traction control. Bringing mine back down from 400, at 360 now. Still testing to see if TCS will function.

From my 2002 service manual:

Torque Management (TM) is a function of the PCM that reduces engine power under certain conditions. TM is performed for the following reasons:

1. To prevent overstress of the powertrain components.
2. To reduce engine power during certain throttle actuator control (TAC) system faults.
3. To limit the engine power when the brakes are applied more than approximately 40%.
4. To prevent damage to the vehicle during certain abusive maneuvers.

The PCM monitors the following sensors and engine parameters to calculate engine output torque.

- Air/Fuel ratio
- Mass Air Flow (MAF)
- Manifold Absolute Pressure (MAP)
- Intake Air Temperature (IAT)
- Spark Advance
- Engine Speed
- Engine Coolant Temperature (ECT)
- A/C Clutch Status

The PCM monitors the torque converter status, the transmission gear ratio, and the extended brake switch input in order to determine if torque reduction is required. The PCM retards the spark as appropriate to reduce engine torque output if torque reduction is required. The PCM also shuts off the fuel to certain injectors to reduce the engine power in the case of an abusive maneuver.

The following are instances when engine power reduction is likely to be expected:

- During transmission upshifts and downshifts
- Heavy acceleration from a standing start
- The brakes are applied with moderate to heavy throttle (with the traction system active).
- When the driver is performing harsh or abusive maneuvers, such as shifting into gear at high throttle angles or shifting the transmission from reverse to drive to create a rocking motion.

The driver is unlikely to notice the torque management actions in the first two instances. The engine power output will be moderate at full throttle in the other two cases.

The PCM calculates the amount of spark retard necessary to reduce the engine power by the desired amount. The PCM disables the fuel injectors for cylinders 1, 4, 6, and 7, in case of an abusive maneuver.


[Modified by TooManyIDs, 9:28 PM 2/23/2003]

 

Now that is an explanation! I also have the LS1 Edit & would like your feed back on the results of your testing the TMS with the LS1 Edit. I'm not real good at using the LS1 Edit so any help you can give me on how to disable the TMS with the LS1 Edit would be appreicated.

 

I hate TM -especially abuse mode (talking about a motor falling on it's face!!!) .I'll eliminate as soon as I get a little further up the LS1 edit learning curve. :thumbs: :cheers:

 

Clancy, leave torque management alone until you see if it kicks in when you spin your wheels with traction control off. The tables you refer to will disable TC. You can 0 out spark retard limit, which retards spark 10 degrees between shifts at WOT.

 

Joe, thanks for the reply to this post also, I will leave the TMS alone until I understand more about it or someone like you suggests that it may be something I should consider. :cheers:

 

Can't wait to get my LS1 edit up & running!!