Purchased a 2002 R53 from dealership not too long ago. Love the car (my 2nd). Previous owner must of been into track racing or was just an upgrade enthusiast, because it has a lot of upgrades, probably up to a stage 2, suspension, oversize brakes, etc. My question is...the dealer claims it has a 17% SC pulley. Is there a way or method to confirm this without a teardown inspection? I have an OBDII, can that be helpful? What about tuneups?

 

Congrats on the new ride...

Have a look here for pulley measurements... should be able to figure it out once you measure yours.

https://altaperformance.com/i-156921...reduction.html

 

If you look at the face of the pulley it will usually say a % number on the front to identify it. If you still don't see it post a pic and we may be able to identify it for you.