stock works good
the stock filter/air chamber has been designed for your engine/vehicle exclusivly. Even the airbox between your 540 and my 530 are different so that says something about the thought that went into this. If you go with a K&N you will allow more dirt into your engine, making 300K+ miles a bit tougher.
Also when you retrofit most of the time you eliminate the "cold air" intake and actually hurt performance and mileage with "hot" air entering the intake syste.
So, to answer your question I cant. I can just post an "oppinion" and allow you to do your own research. Personally I wouldnt bother.
In the days of old, carburetored vehicles with restrictive intake systems there was gain even by flipping the air cleaner lid upside down, more so if you put a hood scoop and even more if you sealed the scoop to cold air.
Last edited by 632 Regal; 10-20-2004 at 07:51 PM.
95 E34 530I V2.37
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