trans wont shift out of 2nd what setup?

I have a 97 z/28 with an a4, and it wont shift out of second, like it goes into neutral or something? I am going to rebuild it, but wondering what shift kit to go with and what kind of stall... it is a little more then stock right now, but going to add LTs, and cam in a week or two. Also maybe a supercharger in the future!
thanks in advance
sean

TransGo and 3000 to 3500.

I agree if your putting a cam in.
I run a TCI 2600 with my stock motor.