I can’t help it, I've wanted a 4wd turbo my whole life and I finally have one, so sorry if my head gets a bit humongous. lol
You can hear the waste gate sometimes when you or the SST changes gears and the blow off when you lift off somewhere after 3 grand. It’s very faint but you can still make it out.
If you want it louder like the WRX and skyline you have probably seen, you need to get a few aftermarket parts put on. Someone correct me if I’m wrong but I think getting these sort of aftermarket blow off valves can do more harm than good if you haven’t added a bit more boost to cope with the stronger springs in the blow off. I think letting the air out like this can confuse the ECU causing it to think more air has gone into the engine then really has which can’t be good either.
But don’t take my word for it I’m no mechanic. lol
Check out this clip, the guy has an evo X blow off and a cone air filter which makes it a lot louder.
http://www.youtube.com/watch?v=q_XawNi7m5Y