I dunno about headers.

your friend has the 4 cyl I assume. Most performance mods I've seen are regarding the v6.

injen and AEM both have Cold Air Intakes, and I think injen also has a Short Ram Intake as well. I've seen some people put dual exhaust tips on the I4.

Other than that people are mostly doing springs, shocks and some exterior stuff like blackhousing and tint.

-w