Originally Posted by WRX2LGT
Yeah Taylor said its the valve flapping open and closed under higher boost. To someone who's never heard it it really does sound terrible. I guess if its normal and the car was tuned for it I will keep it for now. The exhaust is also stupid loud, so may I need to save up for a new exhaust, back to duals, re installation of the 3port so it doesn't do it, and a tune. Just seams like a lot of coin to fix something that isn't broke but I just don't like.
the 3 port boost control solenoid doesnt really have anything to do it. its just the matter of the ewg dumping the exhaust bypassing the turbo to atmosphere without going through any resonators or mufflers.
there are 2 fixes for the noise and 1 fix for the flutter if going back to an internal wastegate is not an option.
1, extend the dump tube back into the down pipe. this solves your noise problem and would be the cleanest/lightest weight. some argue this has negative effects but if you go in at a steep enough angle far enough down the pipe, it shouldnt make a huge difference.
2, get a muffler specifically designed for ewg's. they make em, i just dont remember who.
flutter: most ewgs, come with 2 nozzles. one for the boost line and one to act as an atmosphere pressure valve. theres a way to use a 3 port boost solenoid to attach two hoses to both of these nipples and that somehow equalizes extreme pressure differences and smooths out valve operation. but i havent looked into the mechanics of it.