At what performance level does the stock X throttle body become a hindrance & require ugrading.... & what would you be using when you did?

 

I swapped mine when I did the intercooler piping to have everything even-ish to 2.5". I used the eclipse 3.8 v6 oem throttle body with the evo X connector. It fits the evo x intake manifold and works perfect. I did port match the intake manifold inlet as well to 65mm.

 

Built motor and big turbo.