2006 TBSS Tire size and once in a blue moon shift issue

[Jakes4321]

I am running 17" drag radials at he track and have so for 2 seasons with no worries and started thinkin I should try and change tire size to see what happens. Well I noticed a few things:
1)Why is the tire diameter from the factory wrong?? Am I just misunderstanding it or is it just defined different?


2) When I chnge the settings everything goes FUBAR!!



Also very so often it will blow thru a shift not always but on a rare occasion so I have thought maybe I should lower the shift rpm? Or do I have to lower both Shift and MPH?? The trans seems rock solid and has ZERO issues but on a rare occasion it will do it.

Trans is a FLT level 5 and a vig 9.5 2800-3000 stall. I have changed very little in the trans tune from Stock it seems to work great for me just seeing if anyone can shed some light on the subject. Here are my trans tunes