Just got a 2008 gs i4 and looking to get any mods into it if anyone has any and is located in Arizona let me know.
Thanks for the infoTurbo or bust if you're looking for anything substantial.
A [proper] Cold Air Intake, ported tb, ported manifold, headers, exhaust will likely bump you up from 138hp to 160ish...which would still be inferior to a stock V6. Especially in the torque department.
Use Google, there are still some options available.