Hi there guys n gals, I have just got myself a Subaru Impreza WRX, the suprising thing is that it came with a Blitz dump valve, it only appears to make a noise in the higher revs, the turbo is fine as I got the car pre-checked before I got it. It will be much appreciated if anyone can shed some light on this problem.

 

The turbo doesnt get to speed in till about 3000 revs. If theres no turbo pressure theres no pressure for the valve to dump!