Hello everyone, I just got a 2008 WRX sedan and wanted some help on tuning. I am looking for mods that are effective and not too expensive. I've already got a K&N cold air intake, perrin light weight crank pulley, and subaru short throw shifter. I am planning on getting a custom 2.5" cat back exhaust system within a couple months. My car has 51,300 miles and is a daily driver. I would like to relatively keep the gas mileage.
I've had someone tell me about a wideband o2 sensor and wanted more info about them. I know they tell the engine how much fuel to mix with the air. I've also had someone tell me about head work. I am mechanically inclined and have backyard experience, but never done anything that serious.
Just looking for some tips. Anything is good