Maybe it has to do with me having an E90 and yours being an E93? Maybe the undercarriage is different and you get some type of resonance. Honestly, there is no additional drone in mine. At worst, there is a db or two extra sound at the same exact "drone" frequency as the stock system, under the same conditions. But there is more sound everywhere so this is in character and not excessive.
Thing is that there is no way that you will have "zero" drone with any of these exhausts. Even the stock has some drone in certain situation. I do not find my Sport to have any additional drone over stock. Just deeper and louder sound everywhere. I would guarantee that all of these "race" systems have a ton of drone under the same situations. It would be impossible not to.
Originally Posted by Doru in Romania
that's strange as mine is droning exactly like op says. keep my dct on 2 lines and power mode. it drones all the time in city driving, from 1500 to 2500 or so. after 3000 is quiet. keeping with all settings at max - 5 lines, max power in m mode there is less droning as car tends to accelerate faster and avoid those rpm's. also if i shift manually can avoid droning or keep to minimal. however, never use manual shifting.
2009 Space Gray Carbon Leather E90 with DCT, Loaded except for that stupid cruise control and moonroof. Mods: Fabspeed 200 cell cats, Xpipe w/resonators and no secondary cats, ESS tune, Eisenmann Sport Mufflers, Vorsteiner Rear Diffuser II, SWS8 subs, JL Audio XD400 bridged 2X200W, built in radar