Ok, after driving it around for a while I can say that it does make a difference. The turbo is louder like everyone has been saying, it isn't just people's imagination (unless it is also my imagination. hehe)
Also the car does feel like it pulls harder now. Now my car is mostly stock other than the GR-2 struts I have. The car doesn't tend to lose it's get go in the higher rpm's like it used to. It pulls and keeps pulling fairly smoothly all the way to redline. Now I don't think it pulls as hard as it would if I put in an msd dis-2 ignition, but it is noticable over stock.
I noticed that under the mrt site:
http://www.mrtrally.com.au/shop/ when you click on engine compnents and look at the "PLENUM STL REPL SILNCR WRX 94-96+RS" it mentions that torque and throttle response on high end is improved.
I also got a newsletter from mrt in my email that had this caption:
If you feel inclined and want some power to upgrade your turbo or non turbo car then try this, the resonator inside the right hand wheel arch on your car not only reduces noise but it also sucks power from your car.
This modification will improve turbo car's more noticeably than non turbo cars, but is worth the effort!
Here are two pictures of the GC and GD Impreza Turbo Resonators so you know what to look for, you will need access to the inner wheel arch of your car. The factory airbox will then suck air from the whole inner guard, instead of through the complicated box as shown
It sounds like they are saying it will increase your power, if it does I'm curious how much it sapposedly does or what the combination of removing those two resinators will give you for horsepower and torque improvements.
Anyways, sorry for the long message. Any thoughts on what it would do on the charts or a dyno? 5 hp? 10 hp? I'd think 10 would be pretty steep, wouldn't you guys?
-Ryan