if your concerned about air flow, the 540 airbox has a larger inlet, I don't think it will make much of a difference compared to the 530 box.
The stock filter is very adequite.
JC makes a decent chip until Mark D burns some of the chips he had me test, a rear gear change to a 3:64 helps city drivability big time! No difference in mileage on the freeway either.

Originally Posted by
94BMW530i
Dear god help me!! Not one of the major manufactures has them for a
1994 BMW 530i. Does anyone know of custom ones for a reasonable price? Preferrably under $100? Thanks in advance!
~BMW enthusiast
95 E34 530I V2.37
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