Also, are you referring to just bolting on a TT kit dyno run v a tuned TT dyno run or a NA Z tuned v a TT dyno tuned?
Also, tough question to answer because of boost levels and engine setups. Some people run more boost, others run more open exhausts because they can withe emissions, etc.
Here are a few good threads to read through:
Forced Induction Finished Builds
370z Forced Induction for Noobs...