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2000ssnb
January 19th, 2005, 10:58 AM
In the engine calibration section there is a section about engine torque.
Ane parameter is maximum engine torque. Is this parameter used in
calculations during engine operation or is it a limit that when exceeded
spark timing will be retarded?

Thanks,

Gert

2000ssnb
January 21st, 2005, 03:13 AM
Nobody has the foggiest idea how this parameter is used _ I imagine
it is there for a reason,

Gert

jfpilla
January 21st, 2005, 05:53 AM
In the engine calibration section there is a section about engine torque.
Ane parameter is maximum engine torque. Is this parameter used in
calculations during engine operation or is it a limit that when exceeded
spark timing will be retarded?

Thanks,

Gert
I can't open the sections since I don't have Flashcan yet, but I believe you are referring to torque management. Your right that timing is pulled when you exceed that parameter. There is a belief that 639 is the maximum value that can be put in or the computer will not handle the instruction correctly.

87gmc
January 21st, 2005, 06:07 AM
I would like to find out also it seems when im wot and my trans shifts from 1-2 its like not a solid shift almost like you shift manually from 1-2 wot and let off of the clutch slowly. I noticed when logging my timing is going from like 12 to -3 when it does shift durning the hesitation then climbs back up.

Is there a parameter that controls timing when shifting or does all this have to do with torque management. I would like a firm shift with no lagging. :?:

2000ssnb
January 21st, 2005, 07:49 AM
The max allowed torque is specified in the parameter
section under
- engine calibration
- engine torque
Parameters Max allowed engine torque 350

for any of the stock .tun files of Camaros or vettes.
This seems low to me so I was wondering if there is an
"unwanted" limit.

Gert

GMPX
January 21st, 2005, 11:38 AM
Nobody has the foggiest idea how this parameter is used _ I imagine it is there for a reason,

Gert

It is used by the traction control system (when active).
It affects the PWM output to the EBCM (Electronic Brake Control Module).
The code in the PCM is pretty damn good, there is sane limiters for every value entered, if you entered 1000ft-lb, the PCM will cap it at the maximum that calcuation can work out to anyway which is about 640ft-lb.

As for the trans soggy upshift problem.......checkout the new spark PID "GM.EST_XMSN_DMA" in the latest update you guys will get VERY soon. This shows the timing being pulled by the Transmission torque managment routine, we used to just have a Torque management PID, but there is too many factors involved in that, so we expanded on it a little.

In the meantime, checkout tables - D0801 - D0803. Reduce these by 50% and see how it feels.

Cheers,
Ross

jfpilla
January 21st, 2005, 12:56 PM
Nobody has the foggiest idea how this parameter is used _ I imagine it is there for a reason,

Gert

It is used by the traction control system (when active).
It affects the PWM output to the EBCM (Electronic Brake Control Module).
The code in the PCM is pretty damn good, there is sane limiters for every value entered, if you entered 1000ft-lb, the PCM will cap it at the maximum that calcuation can work out to anyway which is about 640ft-lb.

As for the trans soggy upshift problem.......checkout the new spark PID "GM.EST_XMSN_DMA" in the latest update you guys will get VERY soon. This shows the timing being pulled by the Transmission torque managment routine, we used to just have a Torque management PID, but there is too many factors involved in that, so we expanded on it a little.

In the meantime, checkout tables - D0801 - D0803. Reduce these by 50% and see how it feels.

Cheers,
Ross

You might also try reducing Desired shift times. This will reduce the time it takes to complete a shift. Suggest you try one idea at a time.

GMPX
January 21st, 2005, 02:05 PM
You might also try reducing Desired shift times. This will reduce the time it takes to complete a shift. Suggest you try one idea at a time.

These are used for the Trans Learn adjustments, you are right, you need to change these too for a quicker desired shift time or the PCM will adjust pressures in an attempt to get those shift times.

Cheers,
Ross