From what I've read not really a power gain but provides a more responsive throttle, so a bit more airflow and a bit better acceleration! Noticeable to the guy who drives it 24/7, yes, a rocketship, no. I'm happy with the swap and noticed a little inprovement in idle and acceleration, for your TJ I think you can do it too but you have to see what you can get it from. It's like going from a 42 or so mm tb to a 58 or so mm tb. Noticeable and cheap!
"Who knew coolant keeps the motor cool?"
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