This just started recently I have my trans throttle cable adjusted all the way out. From what I've read it's suppose to stiffen shifts and help the trans last longer by keeping pressure up and not allowing as much time between gear changes. Lately when I stomp the go pedal it will get to redline and stay there until I let go a little then it shifts. When racing a have to feather the at high rpm to keep it from redlining. This is only in pwr mode though. I have a cat back 2 1/2 and intake with boost set right before boost cut(no aftermarket gauge so not sure on exact) car runs great otherwise. I noticed this while racing a z28 from a 60mph roll downshifted good good but wouldn't shift back up until I let the gas go a little( still won though) any help would be great or ill be starting a rebuild thread by the way 87t tranny flushed about 10000 miles ago still red.