wuzup76020 welcome! and congrats on getting a sweet ride. That was a deal. Wish I would have found it...
My WRX was almost fubar-modded when I got it. I found it at a Mom&Pops used dealership. It had exhaust work(leaky), a remote start system(messy wiring, no FOB), BOV (backfired on every shift), COBB dongle left plugged into OBD-II port (tuned?). I've learned so much about my car getting it straight.
With a turbo upgrade, definitely get it checked out by a tuner. Could even be one of those Opensource Tuning guys, as long as they know what they are doing. Ask them to look and see if you fuel injectors are maxed out.
There are some OS tuning cats floating around the forums here, NASIOC, Rom Raider, and a few other sites. See if you can find one local that will look at your ECU for you. Might just cost you a six-pack or something. Subaru Love is legit, its like a brother/sister-hood.