I just put a new 700r4 in my Z. The transmission is a stage 3 with a transgo reprograming kit. My qusetion is, the 1-2 and 2-3 shift is really firm when driving normal. At wot, the 1-2 is firm! the 2-3 seems mushy? I did adjust my TV cable and it firmed it up quite a bit, but it seems the cable is really tight? Should I tighten up the cable even more to firm up the shifts?

 

The transgo kit does a lot to make second gear shift better. In my opinion the third and fourth gear clutch pack needs a few mods to make 2-3 shift feel right.
Make sure the plug that blocks the third accumulator didn't come out. Maybe try a stronger line bias spring and enlarging the third feed hole in the seperator plate.

 

Follow these steps: To adjust the TV Cable skip the book method and do this: Press the 'D' shaped lock button on the adjuster and loosen the cable setting (The black housing that the metal cable is in will move forward). Now, have someone floor the gas pedal while you check to see if the throttle plate is open all the way. Usually they are off a little and will wiggle. Do whatever you have to do to get it open solid. Now, with the pedal still floored, press the 'D' button and pull the cable casing (the black tube) back as hard as you can (putting maximum tension on the metal cable) and release the button. You now have the engine, tranny and gas pedal all in sync at WOT. Mark the cable casing so if for some reason it gets moved you can know where to put it again. The problem with the 'self adjust method' is that it bends things and puts them permanently out of whack. It is also the full TV setting, which is theoretically what the GM method does.

Now after that if you have shift complaints there are two directions to take. One is if the 1-2 seems particularly firm you may need to make calibration changes to slightly lengthen the shift. If there is a real problem with the 2-3 shift it could be an internal problem anywhere from an internal leak or even the quality of the clutches/band.