Q: What are some things i can do to my S4 that would yield major HP gains on a low budget ( >$2k ). Or at-least what are some necessities.
A: well like someone already said, you should get a chip. depending on your milage you just might wait for your current turbos to expire and save up the cash and then get two NEW and higher performance turbos and the supporting mods. in either case you really have to say more than what would raise my hp... like what are you aiming for? 300hp? 400 hp? your car has the potential to be however fast, but you have to be smart about it. why get a chip when if you want new turbos then you should get the turbos first and then the chip.