I have the Perrin Maps for an 08 WRX, Stg 1 & 2 91 and 93 oct. somewhere. After the reflash to stg 1, the low end tq gain was incredible.
For the most part its just like an 06/07 WRX except with a little extra low end grunt {I think they changed something on the engine} Sways, tires, springs, will make gobs of difference. 235/40/18 tires fit with no modifications.
As for springs, be careful what you get. Many of the springs were known to blow the struts easily; even the spt ones. Some people believe it can be caused by a poor installation, but many people think the struts are just plain garbage and can't handle anything lower / stiffer. The pinks seemed to work out good as did the swifts.
You can pick up a set of 09+ take offs from someone that went with coilovers or get an upgraded strut from bilstein {I dont recall anymore what company sold the spring/strut package}..
Also if you go wider tires, get a set of mudflaps. The paint on the 08s were prone to chipping especially with wider/lower offset tires.
Check out 3gwrx.com good site.
Lastly. wax that bitch. The satin white shimmers nicely when clean. I miss my hatch somedays
