having problems with my gt at the mo.. heard blowing noises coming from the engine and found out it was the pipe to the dumpvalve so i changed that and now when i drive the car i hear a whistle as the boost goes up and den a loud blow off when i change gears but thats normal... any ideas why there would be this whistle? i think it may be the dumpvalves fucked and not able to hold back the air until the blowoff? i am stumped 
