squeak, squeal, spray, slip
these are all the words I would use to describe what I hear during boosted shifts.. I have a 96 850r wagon, when giving it full or near full throttle, when the car shifts, it lurches forward and makes a noise that I thought was my bad cbv leaking. it is now replaced with ipd's upgrade kit and it still makes the noise. I thought it sounded like massive air escaping the turbo instead of recirculating properly, but now that I know it is not leaking, i'm thinking maybe a belt slipping?
any help would be fantastic. thank you