you said you had a WOT switch installed and not a window switch, so when you have the N20 armed and floor it your constantly spraying throughout your rpm band. Thats how you buggered up your tranny since the window switch only allows the nitrous to spray within a safe rpm range. Without the window switch you were putting major strain on every gear especially if you were shifting at redline.

 

oh i know what you mean but my trans was f'd up before i even had nitrous. when i floor it though im always atleast 3k and i shift at 6 so im in a safe zone.

 

well at 3-4or5k is safe but spraying at 6 is probably pushing it