Hello All.

I have a problem and am not quite sure of now to deal with it. Hope you guys can help me out with some advices....here goes nothing.

When I floor it so the turbo reaches 1.6 bar od pressure (car is tunned to 300 hp by GrahamGoode so it produces 1.6 bar boost) and then release the accelerator pedal, blowoff valve releases the pressure and a strange sound comes out of the turbocharger like something would bumped a few times to something else. Sounds like metal to metal hit.

Turbo works fine, car works fine, the only thing is this strange noise

Has anyone have any idea of what could it be? I am prepared for the worse and willing to buy new turbo if necesary, but will not spend that much if nothing is wrong...

Please help as I and my mechanics have no idea what could it be