6-Speed Trans in the Track Model

I have been doing a little research because I am considering a 350Z to replace my current ride. I have a questions about the 6-speed manual transmission on the track model. Does anyone know any details about this transmission? Is it a Getrag, Tremec or what??? What kind of horsepower figures can this tranny hold if someone wants to go turbo or supercharger? I have had a Supra twin turbo in the past and the 6-speed Getrag in those cars is good up to 700 horsepower with no modifications other than a heavy duty clutch. I am wondering if the track model Z is that heavy duty. Thank you all in advance. This has been a great source of information.