[Oksana]

Got the mppsk fitted on my 340i. Done 750 miles on it now. Sounds great in sport mode when you’re ‘on it’ but in comfort mode under gentle to moderate acceleration (day to day driving) there is a fair amount of drone that is doing my head in. I’m sure I read somewhere that this disappears after 1000 miles or so but can’t find that post again now.
Does anyone have any experience of this? Or is a bit of drone to be expected even in comfort mode with this app exhaust?

[TK335iMSPT]

Originally Posted by Oksana

Got the mppsk fitted on my 340i. Done 750 miles on it now. Sounds great in sport mode when you’re ‘on it’ but in comfort mode under gentle to moderate acceleration (day to day driving) there is a fair amount of drone that is doing my head in. I’m sure I read somewhere that this disappears after 1000 miles or so but can’t find that post again now.
Does anyone have any experience of this? Or is a bit of drone to be expected even in comfort mode with this app exhaust?

You definitely need to break the exhaust in. It will drone a bit when new. The tone will actually change once you have a few thousand miles on it. My Mperformance exhaust only drones on the highway if I have the flap open. You could check if the flap is operating correctly. That could potentially be the cause if it's not broken in yet.

[bimmer456]

Shouldn't drone in comfort mode as valves are closed. It does open above 4K rpm which will happen more often in S mode when you're on it but not just cruising. It is louder than stock comfort mode. You may need to check if valves are stuck open due to not being installed correctly to the wiring harness.

[aardate]

I read somewhere that the Active Sound Control ASC will amplify this drone, try disabling the ASC and see if that helps. You can easily code it out using bimmercode.

[oksymoroni]

it shouldn't drone in comfort at all. There is some drone in sport around 2k rpm or if you're driving at highway speeds. Once again this is only when the flaps are open in sport/sport +. Comfort should be drone free regardless of speed

[CajunBMW]

Originally Posted by oksymoroni

it shouldn't drone in comfort at all. There is some drone in sport around 2k rpm or if you're driving at highway speeds. Once again this is only when the flaps are open in sport/sport +. Comfort should be drone free regardless of speed

Agreed. I have had my mppsk for 20 months now. No drone in comfort mode. Some drone at 1800-2k in sport as stated by many. I don't race the car, but if I want to try to avoid the drone in sport, I either use sport and then shift the shifter to the left to put it in sport for shifting or use sport+. The net result is it raises the rpms a bit and keeps the car from that 1800-2000 rpm drone zone.

[CajunBMW]

Originally Posted by oksymoroni

it shouldn't drone in comfort at all. There is some drone in sport around 2k rpm or if you're driving at highway speeds. Once again this is only when the flaps are open in sport/sport +. Comfort should be drone free regardless of speed

Agreed. I have had my mppsk for 20 months now. No drone in comfort mode. Some drone at 1800-2k in sport as stated by many. I don't race the car, but if I want to try to avoid the drone in sport, I either use sport and then shift the shifter to the left to put it in sport for shifting or use sport+. The net result is it raises the rpms a bit and keeps the car from that 1800-2000 rpm drone zone.

[MmmmmM2]

Mine doesn't drone at all in comfort mode so must be some issue.

[Oksana]

Originally Posted by aardate

I read somewhere that the Active Sound Control ASC will amplify this drone, try disabling the ASC and see if that helps. You can easily code it out using bimmercode.

I did this and it definitely helped some:-)

[Oksana]

So to clarify, there is no drone when cruising. I just did a long motorway journey with cruise control set a 70mph and there was no drone at all. The drone is there on gentle acceleration in normal driving acceleration. I live in Milton Keynes where the roads are all National speed limit separated by roundabouts at Apx half mile intervals. So it’s constant acceleration from 20mph up to 60-70mph then down again, then accelerate again etc and it’s on the acceleration that it ‘drones’. I’m not sure if drone is the right word. The noise the exhaust makes is a bit louder than stock (not massively) but it is at a resonance frequency that Is just unpleasant! and gives me a headache after even quite a short journey. It’s not the flap because when I put it in sport mode it is noticeably louder.

[obzen]

I second the active sound design. I coded mine off last week thinking it was already off because it was set to 'unassigned' value and figured they should have coded it out from factory given mppsk.

[Wires]

Doesn't the MPPSK lose that midpipe resonator? It's purpose in life is to eliminate part throttle drone.

Tone will change over time, as well as with temperature/humidity. On hotter days, my AA exhaust is a lot louder than colder days.

[Londoner]

I noticed a fair amount of drone initially in comfort but it seemed to fade away after a week or so of driving.