welcome to the forums:bigthumbsup (always nice to see someone from the boston area)
anyways to your question, you should get the same performance, the thing about throttle bodies is they dont really add as much hp as they advertise with the new edge v6s. the reason for this is that the stock throttle body is 65mm.
with the aftermarket you will make an extra 2-5hp at most. the big thing about the throttlebodies that makes them popular is they adjust the throttle response of the car.
hope this helps
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