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Slow 2-3 Change in Manual Mode (Tap up Tap Down)

My main complaint for the 6L80e is the very slow 2-3 shift in manual mode. This will be the first area I will be focusing on. The blue line in this datalog clip shows the ignition timing during a 2-3 change. I have overlaid a sport mode change and a manual mode change over the top of one another. You can see that the amount of ignition retard and the duration of the retard is far greater when in manual mode. The sport shift takes 335 milliseconds and the manual shift takes 935 milliseconds.

I have discovered why the 2-3 shift takes so long in Tap Up Tap Down (TUTD) mode; It’s due to the fact that the torque converter is commanded to lockup on 3rd gear apply when in TUTD mode.

In sport mode (Pattern A) you can see that the TCC is never applied in 3rd, whereas in TUTD mode it is applied (Both circled in red). So I assume that the ECU is retarding the engine power to allow the TCC clutch to engage on the 2-3 change.

My solution was simple: Copy the TCC tables from sport mode to TUTD mode.

Ref. tune2