N55 FBO Exhaust Options to quiet it down?

[drummr8]

I have a 2012 35i. I've installed a VRSF downpipe and MHD. The exhaust sounds pretty good, but when you apply too much throttle, the change in sound when the valve opens is obnoxious. I tried propping the valve to always be open so it'd be consistent, but then it's just too loud all the time.

What is a good solution to quiet it down just a little? Ideally I'd quiet it down some and then prop the muffler valve open so the sound is consistent.

[nodemgr]

Seems like you need another muffler. How's the smell with the catless?

[drummr8]

Originally Posted by nodemgr

Seems like you need another muffler. How's the smell with the catless?

but what muffler would be quieter than stock? aftermarket mufflers are usually to get more sound not less lol

The smell is not great. It's much more tolerable on my 335xi which still has secondary cats in place. I'm wondering if I should install a high flow cat in the X5 and that would help both the smell and the sound? The smell isn't awful, but it isn't pleasant either. My wife hasn't complained other than one comment when I first modded it, so it must not be too bad

[nodemgr]

Originally Posted by drummr8

but what muffler would be quieter than stock? aftermarket mufflers are usually to get more sound not less lol

The smell is not great. It's much more tolerable on my 335xi which still has secondary cats in place. I'm wondering if I should install a high flow cat in the X5 and that would help both the smell and the sound? The smell isn't awful, but it isn't pleasant either. My wife hasn't complained other than one comment when I first modded it, so it must not be too bad

Maybe you can put another muffler in-line with stock? Some slim small muffler perhaps...unfortunately I'm not sure there is a way to know unless you try. High flow cat would definitely help.

Or, maybe there is a way to limit the exhaust flap opening all the way? Maybe open it 25% or something.

[zoom750]

Try adding a resonator in the midpipe. Something like this...

https://www.amazon.com/Vibrant-1792-...ps%2C79&sr=8-4

Just make sure you have the space and the correct diameter.

[drummr8]

Originally Posted by zoom750

Try adding a resonator in the midpipe. Something like this...

https://www.amazon.com/Vibrant-1792-...ps%2C79&sr=8-4

Just make sure you have the space and the correct diameter.

I've read that resonators only help with rasp and/or drone, but not general loudness... I'm skeptical that a resonator would help. Do you have personal experience with adding a resonator to reduce loudness?

[zoom750]

Originally Posted by drummr8

I've read that resonators only help with rasp and/or drone, but not general loudness... I'm skeptical that a resonator would help. Do you have personal experience with adding a resonator to reduce loudness?

No. I haven't installed a resonator in my car, but was considering it for myself. It sounds like you're leaning towards a muffler. This might be what you're looking for.

https://www.amazon.com/dp/B000COTCI0...axlechassis-20

[drummr8]

Originally Posted by zoom750

No. I haven't installed a resonator in my car, but was considering it for myself. It sounds like you're leaning towards a muffler. This might be what you're looking for.

https://www.amazon.com/dp/B000COTCI0...axlechassis-20

Interesting, I've never heard of running an inline muffler in addition to the one by the tailpipe... Didn't even know it was an option. Makes sense though.