I am not really an expert but i think that to run 12 psi you will need to change the compression ratio in your engine. I am also not sure but i think you mean an 18G turbo. That is a pretty big turbo for what your doing. It'll work buit it may be a bit laggy. I think maybe 6-9 psi will be all you car would be good for. If you do this, you will need manifold, for a turbo. Uppipe, downpipe. Injectors, Fuel pump, Engine management. There is probably a list a mile long. Do a search in the AFTERMARKET TURBO forum and maybe in the CONVERSIONS forum. They will be able to guide you a lot better. I am not 100 percent sure about what i've said and if i'm wrong i am sure someone will tell you. I-club is a good place to start. Welcome to the club, and good luck

 

Frankly, if you couldn't afford the difference between a 2004 RS and a WRX, you shouldn't be trying to turbo the car. It's really not a motor conducive to running boost on. If you are indeed trying to put an 18g turbo on it, it's going to be almost impossible to do safely without standalone engine management. If you have REAL engine managent, with good control over fuel, boost, and timing, you can run up to 10 or 11 psi on a properly sized turbo. But, real engine management + good turbo kit, including turbo, up and downpipes, intercooler, injectors, fuel pump, etc. is $3-4k, and still won't be as relaible as a factory turbo motor.

Basically, instead of trying to turbo the car, just start saving for an EJ20 swap from a good shop. It's easier and cheaper in the long run.

 

I kind of thought the same thing. Also I noticed that his rs is an 04'. Which unless it has really high miles is still under warranty. I know i have probably voided a lot of my warranty,most of it is still intact. By doing this he will be voiding his entire drivetrain warranty. Ban is correct. I think you should sell the 18g and save for a WRX or STi.

 

Warranty schmarranty. Go fast.

 

They don't make RS turbo kits.