could it be a sensor or somthing that controls open/close loop? Maybe when the car is warmed up and you go WOT it stays in closed loop? IF it stays in closed loop the tune would be off right?

You say it drives good when the car is cold (open loop), but drives like an NA when its warmed up (closed loop). Maybe the tps not telling the ecu to go into open loop. I'm not sayin thats what it is just throwin the idea out there.

hope it helps.