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Treurentner
August 25th, 2010, 10:19 PM
Hi,

i recently saw on part throttle acceleration, that the transmission torque limits are pulling around 15° timing until the TCC is locked, {GM.EST_XMSN_DMA} is logged, see attached file.
Usualy the B1902 is responsible for the amount.
Is there an other way to avoid this - exept altering this table and why this happens with unlocked converter only?
What other subsystems use B1902 and are affected while changing the table?
The 411 with 12221588 OS is used, are the other possible OS working the same?
All drivetrain/tranny torque limits in the .cal are already cut off or set to max.

The engine and the whole drivetrain were build to have the stock hp more than doubled (:grin:), and so it is important for the A4 (LevelVI) reliability to keep the torque reduction for the shifts and the abuse modes fully functional.

Regards

Marco

joecar
August 26th, 2010, 03:09 AM
Hi Marco, what value do you have in B1901...?

Treurentner
August 26th, 2010, 05:17 AM
Hi Joecar,

these are the the values:

Parameters Value
{B1901} Max Allowed Engine Torque 867.010558 Nm
{B6601} Axle Torque Limiting Disable
{B6615} Max Torque, Front Axle 56829074.034764 Nm
{B6616} Max Torque, Rear Axle 56829074.034764 Nm
{B6617} Max Torque, Front Prop Shaft 56829074.034764 Nm
{B6618} Max Torque, Rear Prop Shaft 56829074.034764 Nm
{B6619} Max Torque, Trans Input Shaft 56829074.008301 Nm
{B6620} Max Torque, Trans Output Shaft 56829074.008301 Nm
{B0401} BTM Enable RPM 12799.023438 RPM
{B0402} BTM Disable RPM 12798.046875 RPM
{B1903} TCS Shift Duty Cycle 13.007813 %
{B1904} TCS Delivered Torque Duty cycle 30.000000 %
{B1905} Stall Speed 3000.000000 RPM

Im pretty sure that the engine excedes the 867 Nm, the MAF is maxed out under WOT
@ 4.7k with F1R and 4" pulley, rev limiter @ 6.8k :good: