For those who haven't build cars up, you may not understand the question so I can see where some of the responses come from. Here's your chance to learn...every single auto tranny has a limitation on how much power it can handle. In a manual car your clutch has a limit as well which is why people upgrade the pressure plates/clutch etc..etc...
The smart thing to do is figure out what that number is. I'm sure the standard bolt-ons are fine, I am curious as to where the limitation is. I'm sure as cars are tuned and built up some of the shops will realize what this limit is which is why I put the question out there. It's always good to know how far you can go with your car before you have to upgrade certain components.
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Chris
Current: 2014 WRX Stage I + SPT / 2013 Hayabusa 202HP
Former:09 370Z 7-AT PW/Ark Type 2 exhaust/Evo R lip/TSW Nurburgring carbon