[SDKmann]

Well to start an intercooler attached to a air box would do nothing. A pulley driven fan really wouldnt do much either. The sensor in the airbox does control how much fuel is injected but if you already have a fogged air box then theres not much you can do DIY wise to squeeze out more performance from higher air flow. Also to adress your "exhast" that you have, by exhaust do you mean an aftermarket muffler (I really hope its not a fart can...) cause if its just a muffler then your not getting much out of that either. The rest of the exhaust system needs to be replaced with something that is free flowing if you want a real difference. Its time to spend some money bud. I can see that E46 bumper and your chrome rims from a mile away and I would sell those asap and get some performance parts on. A good way to start would be to get a CAI, you can get one for $100 and that would be the only way to increase air flow now. I would also go for a nice set of springs. I would personally get a set of H&R springs and a set of BavAuto ones wouldnt be bad either. From there go to sway bars and then replace the rest of the exhaust system. Get the bling off and the performance parts on on and you will be golden.