Dude, loose dem manifolds/cats! You will unleash a ferocity of sound of similar caliber. You can always add cats... Your M54 will definitely breath better with that supercharger too! The factory manifolds choke it for sure.

Agree, that e39 sounds menacing to say the least!

Quick side topic question.... what size injectors are you running on your setup?

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2005 X5 3.0, 6MT, Alpine White on Truffle Brown, Sport, Preim, and Cold Weather, Alpina Stainless Headers, AFe Intake, UUC SSK, OEM 87's, 3.64 Differential Swap,Performance Modified Euro 2 Tune, UUC LTW Flywheel and HD clutch, Bilstein B12 Suspension kit
Future mods ZHP/Schrick Cam Shaft upgrade, Operation code name:Doppelschrauben-Kompressor

Wife's Ride: 2011 e70 X5 351 M///Sport.

Also in the fold: 2004 X3 3.0, 6MT, Black Sapphire on Terracotta, port, Premium, Cold Weather.