Should I get an upgraded ECU from VMS or an Absolute performance chip for my 2004 AWD 2.5T?
You can start by purchasing a drop-in K&N filter to replace your paper air filter. If you want to spend a little more, check out EuroSport Tuning (eurosporttuning.com), IPD (ipdusa.com), ViVa (vivaperformance.com) or Elevate (elevatecars.com) for performance parts and other accessories. You can also join a forum for more info. The most popular is Swedespeed (swedespeed.com) Performance software is expensive. You can get a CAI and an exhaust system to start. Right now I'm just running a drop-in K&N with a catback exhaust with no resonator and it improved my performance slightly, considering ViVa's CAI or EuroSport Tuning's CAI for $199.
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