Kewl deal. Interesting, by removing the resonator and putting in the X-pipe, your exhaust at higher rpm has a similar "raspiness" as the E46 M3, but not as pronouced.

E46 M3 owners complain about the rasp at the higher rpms, but I guess 2004-05 have less raspiness....The cheapest solution is to replace the BMW resonator system section with one that has a resonator on both pipes. The M3's OEM resonator only has one resonator on the driver's side pipe and the passenger side pipe has NO resonator.

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