TUTD shift speed test 1 — Too high

Tested my 2008 Cadillac STS-V with the LC3 Supercharged 4.4L DOHC VVT V8 this morning cold, low on fuel.  Today’s experiment was to add an auto-shift at the top of the tap-up/tap-down shift for 2-3, so I can lock the transmission into 2nd gear for testing, but then have it auto-shift at redline and avoid either having to pop it out of sport mode and back in to get it to auto-shift, or just hitting the rev limiter in 2nd.

For this test I also restored the stock calibration higher advance at high RPMs.  I recognized that what this higher advance does is offset the beginning of IAT2 retard, with the net effect of hitting closer to the ‘ideal’ timing.

TUTD Shift Speed miss 2013-06-20 hptuners

Unfortunately, it never shifted and just hit the rev limiter in 2nd.  I will have to recheck the calibration for commanded shift speed and rethink why it didn’t shift.

TUTD shift speed miss 2013-06-20

Max boost of 9.5-10 psi, and a nice max delivered torque of 468 lb -ft at 3530 RPM, max calc hp of 548.8 hp at 6580 RPM.

TUTD shift speed miss 2013-06-20 VD

The Virtual Dyno shows a steady 377 WHP from 5500 on — looking a lot like the car needs more something to keep raising torque/hp after 5500 RPM.  I would like to see the car get to 440 WHP in 2nd gear tests like this one (!)

Conclusion:

Today’s test was not successful in changing TUTD shift behavior.  The car put up good numbers, although the Virtual Dyno WHP continues to stay below goal.  Restoring the additional timing at high RPM seem successful.  I have recalibrated the TUTD for the next test.

Update:

TUTD timing vs retard b

Pulled 0.5 of timing at the two points where KR is coming up, and added some timing at 6800 RPM to push up the last bit of the curve.

 

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