Right. This will sound very silly, but! I've got a k1 totally standard apart from the forge spacer which I fitted around an hour ago. It does give you a louder noise from the turbo like pressurised air coming through a small hole. But I noticed earlier due to some sloppy gear change that: when you change gear, instead of lifting of the throttle, depressing clutch, change gear and then up clutch, down throttle. If you dip the clutch jus a second earlier and then come off the throttle. You can hear the flutter or pigeon sound (Whichever you call it) not very loud but it there. But doesn't do it if you change gear normally. Very strange. But forge spacer Is good if you don't mind hearing the 'dump' even under low throttle. Is still quite noisy when your not booting it