I think everyone steered you in the right direction but to my thinking THEY MISSED SOMETHING! To me it is the most important performance upgrade there is for the car, get the DDM Works Race backbone, it does not make the car faster, it just makes it so you can drive it faster, you can order from here they are a supporting vendor, very easy suspension upgrade takes maybe an hour start to finish, they also sell the only CAI for this car that works but it comes with and intercooler so it is expensive. I would go with the Wester's tune instead of the GMPP more bang for the buck, but that's just me.