I was talking on terms of power, exhaust and intake... not headers, yet. I understand I will not get the 170 whp... without swapping the engine. Suspension, sway bars, wheels and brakes, are on the list...
I was also talking about exhaust and intake. First and foremost, you'd have to find an exhaust that fit; that wasn't too short because it was expecting to bolt onto a downpipe instead of directly to the headers. Secondly, all an exhaust will do will make your car louder; it won't gain you huge horsepower. An intake will, quite literally, kill your car. The only reason I am running an intake is because my car got tuned RIGHT after I put it on. In fact, on the baseline run on the dyno for my car, the car automatically adjusted its timing, causing a 7 to 10 horsepower drop, before the car could knock due to how lean it was running. Intakes on N/A Subarus are NOT a good idea unless you're a fan of running really lean and knocking your own engine to death. So, an intake might seem like a cheap mod for some cheap horsepower, however, the only way to make it work without replacing your engine is to get a tune from a reputable tuner. This can cost $500 for a base tune with open source software, and that's the low end as not every tuner can open source an N/A GH. You're most likely looking at $700 for a Cobb AccessPORT and then more money for the tune, just to run a $100 intake.
Headers won't really help either; you're already running equal length headers rather than the less efficient unequal length on the turbos. However, the Subaru community, which I am looking to get out of now because of what it is turning into, likes their unequal length headers as they provide that "Subaru rumble." Again, though, the turbo cars are more willing to sacrifice their horsepower for a particular sound because, just like everybody else in the community, they want to be different after going stage 2 with their exhaust and downpipe, and because they're stage 2, they have power to spare.
I don't mean to be a buzzkill, or to rain on your parade, but you have to realize I don't throw something on my car without doing the research first. My car, for a variety of both tuners and aftermarket part suppliers, has been a mini-testbed for parts. I know what works, I know what doesn't work, and 95% of the time, I know WHY it doesn't work. I'm just trying to keep you from damaging your car. I don't think your wife would be very happy if your inexpensive little intake mod suddenly requires a brand new engine from Subaru... out of pocket.
