People have always said if you get a shift kit to becarefull about which PCM upgrade you get and the w-body store one is the only one that seems mild enough to still be able to have a PCM upgrade and not have to worry about messing up the trany.

 

Oic see what your saying now, slow sometimes

what they are talking about is some of the pcm upgrades will allow you to change the trans. presure to make the car shift harder/faster. what they are telling you is not to have both at the same time.

exampel

in the hypertech computer you can change your line presure to 25% 50% belive it is 100% harder then stock
If you have ashift kit it changes the peramitors from you stock trans. already so DO NOT DO BOTH!!
It will result in Damage to your tranny. it will cause it to shift WAY to hard and could cause breakage in the tranny and also could cause other things to fail like gaskets etc..

but the Thrasher kit will work with the pcm you have and if you buy the programer you just make sure you dont reset the trans presures to be diffrent then what they are stock