what? I've got a .82 A/R I could install....that'd be sw333333333333t....lol
basically....you need to set a budget on the car....THEN, we can go thru a list of what you can do to the car.
Otherwise, just like any WRX or STi...sky is the limit.
Power
Reliability
Cost
Pick TWO.
I have gone for cost and reliability...most of the time....i tried to mix power in and made decent power but reliability was iffy...eventho I never suffered any kind of failure...decent power being 165hp/225tq at the wheels. (~240/320 crank)
Right now, mysetup:
TechWorks Engineering EA82T Header and Downpipe for the stock turbo (header fits ANY IHI/Mitsu turbo deisned as bolt on upgrades for WRX-STi, DP is specific for the stock VF7 only)
A custom intake featuring JDM Straws.
Toyota Celica ST-165 Air-Water Intercooler unit.
STOCK boost.
2.5" from the downpipe back w/no cat and just a large resonator. Sounds great.
It puts down 130hp/130tq at stock boost in the cold weather. Normally its ~115/140. (dunno why the TQ varies w/temp as compared to the HP)
Right now the real weakpoints for these engines are the headgaskets and lack of fuel to run more than 11PSI of boost safely for long ammounts of time. any more than 12 psi results in a lean condition which means BOOM goes the headgasket...or a hole in the piston....I've NEVER had piston issues....but I've ran into headgasket problems.....ever since I've been careful about the boost and not letting it run lean...ive not had any problems.
Once you can get the right amount of fuel in per boost...and no detonation on good gas...I think the headgaskets are fine as long as the rest of the engine is in a really good state of operation....the cooling system is MOST important.
Right now I am in the process of talking to SOA to try and convince SOJ to make the mulitlayer metal headgaskets for the EA82 and ER27...as they already make them for ALL of the EJxxx/EG33D/EZ30x engines...
I am waiting to hear back from ARP about head studs....the stockers wont hold more than about 85~95 ft-lbs before breaking/stripping the block...and we should really run 105 on a stud that doesnt stretch on the stock gasket so it'll hold above 19 psi....so far no luck. The EJxxx ARP set is WAY too long even for the long bolts...and the EVO studs are 1/2 inch too short for even the short bolts.
Otherwise, the first place to start for power is a conefilter on the MAF, catless exhaust and no muffler. Even with the stock DP w/out cat...and a 2.25~2.5 inch off the stock DP, the car makes good power over stock.
an intercooler is a MUST....a good one has 30tq gain over stock...no HP until you add bost. Again, DO NOT go over 11 psi unless you add more fuel with larger injectors or an extra one.