I recently bought a 2010 Cobalt "Xfe". During the process of looking for a car I found a 2010 Cobalt SS TC. Unfortunately I could not purchase it...But fell in love with the style of the car. For a new Cobalt enthusiast I would like to know what Upgrades should I do to make this Xfe into a feared Xfe. I already put a Flowmaster 40 on just yesterday. What should be my next step?