The hard plastic "intake muffler" on the E53 mates to the air cleaner in a different direction and at a different height than the rubber "upper intake boot" on the E46. The diams are prob the same, but I doubt this is going to work.

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12 E70 3.5i xDrive
03 E46 330i ZHP
01 E53 3.0i
98 E36 323is
12 Audi A4 Quattro
79 Triumph Spitfire
73 MGB