[2018Aloy]

Hey guys, hope everyone's well. Have a question that I'm sure had been beaten to death, regarding downpipe choice. My situation:

1. MPE exhaust produces drone around 3k, in the low 300 Hz range. Pretty head-rattling for long drives, if you choose to stay in 6th

2. Currently stage 1 tuned, Wagner Evo2 fmic, CTS intake. Want to tune to BM3 Stage 2, with cold start delete, CEL clear.

Question: Would a catted downpipe make that 300HZ drone worse/louder? Is any particular brand that would slightly alter drone frequency? Everyone mentions "more character" or "deeper" sound, but no reference to drone instensity. Any advice would be appreciated.

[CalAcacian]

Yes, if your current setup is on the stock cats and you are moving to a sport cat, any drone you have will be more noticeable. I have it on my setup running a Dinan exhaust and I have run several permutations of the setup:

1. full stock
2. stock cat and muffler with Dinan resonator delete.
3. sport cat with stock muffler and Dinan resonator delete.
4. sport cat with Dinan muffler and Dinan res delete (current setup)
5. sport cat with Dinan muffler and stock resonator.

The current setup has the most drone, but I just deal with it and use a valve controller to keep the exhuast valve closed for most normal driving.

[2018Aloy]

Originally Posted by CalAcacian

Yes, if your current setup is on the stock cats and you are moving to a sport cat, any drone you have will be more noticeable. I have it on my setup running a Dinan exhaust and I have run several permutations of the setup:

1. full stock
2. stock cat and muffler with Dinan resonator delete.
3. sport cat with stock muffler and Dinan resonator delete.
4. sport cat with Dinan muffler and Dinan res delete (current setup)
5. sport cat with Dinan muffler and stock resonator.

The current setup has the most drone, but I just deal with it and use a valve controller to keep the exhuast valve closed for most normal driving.

thanks for the reply. I'd keep valves closed to keep it down, just wanted to look into stage 2 tune. I love the way the car's throttle response feels now, but only in Sports+ valves open. Currently I measure average of 76db of drone on highway drives, wouldn't want to make it go past 80db (with valves closed). So VRSF 300 cell wouldn't be any different sounding than Wagner 300 cell or Fabspeed? No tonal different, just build quality?

[DanG]

Originally Posted by 2018Aloy

thanks for the reply. I'd keep valves closed to keep it down, just wanted to look into stage 2 tune. I love the way the car's throttle response feels now, but only in Sports+ valves open. Currently I measure average of 76db of drone on highway drives, wouldn't want to make it go past 80db (with valves closed). So VRSF 300 cell wouldn't be any different sounding than Wagner 300 cell or Fabspeed? No tonal different, just build quality?

Do you have ASD disabled. That was the source of my drone. Much nicer with ASD gone. (I have the ASD bypass harness).

[2018Aloy]

Originally Posted by DanG

Do you have ASD disabled. That was the source of my drone. Much nicer with ASD gone. (I have the ASD bypass harness).

Yes, ADS is off. I disabled it in Bimmercode.

[CalAcacian]

Originally Posted by 2018Aloy

thanks for the reply. I'd keep valves closed to keep it down, just wanted to look into stage 2 tune. I love the way the car's throttle response feels now, but only in Sports+ valves open. Currently I measure average of 76db of drone on highway drives, wouldn't want to make it go past 80db (with valves closed). So VRSF 300 cell wouldn't be any different sounding than Wagner 300 cell or Fabspeed? No tonal different, just build quality?

I haven't been able to notice a difference between brands, with the exception of the Fabspeed (which I run) retaining the original brace which (to my memory) the VRSF does not. I believe the Wagner does have the brace.

[samsamdar]

Honestly dude, you just gotta get of the MPE. I'm currently running a VRSF catless DP and Remus exhaust and the drone is honestly non-existent with valves closed. Way better than when I was running MPE with stock DP. Idk how BMW screwed up so badly on the MPE for this car lol (mine literally cracked off the car at one point)

[restonot]

I agree that brands such as VRSF, Wagner, and Fabspeed may not have significant differences in sound, except that Fabspeed retains a specific bracket.

[2018Aloy]

Originally Posted by samsamdar

Honestly dude, you just gotta get of the MPE. I'm currently running a VRSF catless DP and Remus exhaust and the drone is honestly non-existent with valves closed. Way better than when I was running MPE with stock DP. Idk how BMW screwed up so badly on the MPE for this car lol (mine literally cracked off the car at one point)

I received the MPE for free as a replacement of dented stock exhaust , happened during car delivery by dealer's flatbed. I know, everyone's worst dreams....but that's another story. I like how deep and gnarly the MPE is, valves open (windows too Pretty much how I drive all the time, once the car warms up.
Would love to address the drone issue and if not successful, may just put on a 300cell DP and run it with valves closed. Should be around same dB level at drivers position.

[2018Aloy]

Originally Posted by restonot

I agree that brands such as VRSF, Wagner, and Fabspeed may not have significant differences in sound, except that Fabspeed retains a specific bracket.

Thanks, soooo what is reason for such price difference? Build quality? Of longevity of the DP?