What is you're torque? HP doesn't kill a transmission. TQ or lack of driving skill kills transmissions.
A Z32 isn't a bad choice.
-easier to source out (this statement is all relative to who you are and where you live.)
-parts for the Z32 are readily available from the dealership/aftermarket
-Mazworx is your friend, as they take all the engineering out of the equation.
The 350z six speeds are garbage. When they first came out they had a huge recall where tons of them were giving out with less than 20k miles on them.
A T5 Transmission is a feasible option, but also keep in mind that mustang guys often fly through these guys as well, anything above 350 ft. lbs starts to stress a T5. A GREAT option is a new OEM mustang cobra R transmission. I've personally seen some of the worst abuse I've ever seen with a chassis pushing over 550 ft lbs. It finally gave, but it took over 3 years to finally give (of all things to fail...5th gear did). They are a bit pricey, but not really any more than a brand new nismo 6 speed.
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