I removed the intake silencer in the fender well of my Legacy GT. It wasn't too complicated. I don't know if I noticed any performance change other than maybe just thinking
that it felt more peppy. I'm running an Amsoil TS-74 drop in panel filter in mine, which is the same as what the SVX would use.
At idle, it sounds like there is a vacuum cleaner running under the hood. It's not a woosh sound, and it's not a high pitched sound. It's kind of like an 'air hum'.
It goes away just a little above idle speed. At WOT you can really tell it's sucking in the air. It makes a different type of sound that is also hard to describe. Maybe on an SVX it'll be different. Let us know what you think.