The funny thing about chargers you need to look at one in pieces before you understand how it comes together! I would be inspecting sealing strips and scroll conditions as the strips wear down so does the scroll. You find glazing on the inner casing where the scroll itself has wore against the inner casing. At this point the seal strips could fall out of the seats as there is no seat left.
There is no real effort to change out all seals and strips, but porting is another story as discussed already!
Look at my charger pics its a RS4 spec or the limit of output as I have only three support prongs on the outlet.
To get this ported to this standard its about 700 Eurs from Germany check there Site SLS.
I might take my spare charger out and post pictures if you want Kai?
Jay
I'm sure we can get rebuild kits alot cheaper for a stock charger
