Yesterday, in the fourth round of my race, I stalled up the converter preparing to launch and when I launched, I felt the truck kind of slip forward then take off really slow. As I went down track, I noticed that the truck wasn't shifting so I lifted just before the 1000' foot cone and coasted the rest of the way. In doing that, I still crossed the finish line at 73 mph and 15.26 seconds (I normally run 14.0's). I drove back to my pit thinking I had broken something. No code was thrown.
After letting it sit for a while, I went to put it on the trailer and I took a little drive and everything shifted just fine. I even stalled it up and did a full throttle launch and it shifted into second fine. In thinking about after the fact, the best way to describe what it felt like was a motorcycle leaving a stop in the wrong gear. I think I may have left the starting line in third gear rather than first somehow which explains my speed and ET despite not shifting.
Some background...I recently re-wrote my PCM several times trying out different tunes and operating systems. During this race, I felt at times that truck was kind of re-learning itself. A similar shifting issue happened once before about three years ago but a code was thrown for shift solenoid B. I had the code cleared and the person that cleared it said nothing was wrong and that modified transmissins do this often. My trans currently has a PI 3200 stall converter, Transgo shift kit, corvette and billet servos.
Any help or ideas would be appreciated! My tune is attached for review and any pointers anyone may want to give. Thanks!
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