[TalonTsi97]

Honestly a 4g63 head doesn't need porting either until you making some pretty good power. Head studs though are a must, maybe at your power level it'll be good peace of mind but beyond mid 400whp your gonna definitely need them.
arp head studs, smallest i'd go would be in the 800cc range but would probably just grab 1000cc injectors, walbro 255 fuel pump, licp (ets, nisei, jmf) wouldn't buy a 2 piece one from my experience, 3.5" fmic core (ets, ebay [surprisingly], jmf, buschur [need his own licp with it tho], etc), tune (K.P. Tuning or peteyturbo hands down), kelford 272s, valve springs & retainers (kiggly, supertechs buschur), if your staying stock frame turbo i'd also look into a nice o2 housing (jmf o2 dump, titek, megan)

It's easy to make an evo go fast and for not a lot of money, well a lot of money but in comparison to other cars it can be done fairly reasonable. If your smart and plan out "used" and new parts and shop around you can really get some good bang for your buck without even grabbing a bigger turbo. Have fun with the car for a bit on the fast spooling good whp IX turbo and then debate what you want to do before spending another grand + on a bigger turbo.