Did you buy the high mileage ///M with a Gruppe M for sale recently? (IIRC from Kensington) That would explain why you might want an OEM intake and exhausts.
It would be interesting to hear what you find in the way of inefficiencies from the OEM induction system, presuming you are planning to take measurements...
It would be interesting to hear what you find in the way of inefficiencies from the OEM induction system, presuming you are planning to take measurements...