S550 stock exhaust to sound like S560 pop and crackle?
Member
Joined: Apr 2016
Posts: 172
Likes: 45
From: Houston, TX
2017 S550 coupe, 2013 E550 coupe, 2008 Tahoe
Solved! So there are 2 outlets on each muffler. In reference to a single muffler, one outlet has a flapper/damper in it and the other one does not. You can see this with a flashlight looking into the exhaust pipe. I want both outlets open. I connected the two vacuum lines in the trunk (bypassing the relay) with a 1/4" barbed hose union. Flapper/damper on both mufflers are open with car off and on. When disconnected you can hear the loss of vacuum and the flapper/damper closes. The pop/crackle is not achieved from what I can tell but at least I know all 4 exhaust pipes are open and not just 2. I did not check to confirm that with relay hooked up factory style, if flapper/damper is closed in eco or open in sport mode.
Last edited by wheatswake; Aug 14, 2023 at 12:31 PM.
Junior Member
Joined: Jan 2005
Posts: 60
Likes: 6
From: Palm City, Florida
2015 MB S550 Coupe, 2018 Carrera T, Ford F150
Yes, I see that you did not bypass the relay, but you are on the right track now. Simply join the 2 vacuum hoses of differing diameters with a coupling and you’re done. There will be no crackles or pops because that requires ECM intervention. But the exhaust will have a very satisfying tone.
Last edited by cyberay; Aug 14, 2023 at 10:59 AM. Reason: Update
Member
Joined: Apr 2016
Posts: 172
Likes: 45
From: Houston, TX
2017 S550 coupe, 2013 E550 coupe, 2008 Tahoe
Cyberay,
Think you are looking at dbrown pics. I did bypass the relay. I just wonder if sport mode actually does open the flapper/damper when connected factory style to the relay. I never checked. One other thing I found while doing this is I thought the main batt. was under the spare tire tool/3D sub area. I have the 3D sub. My batt. is behind the backseat carpeted panel.
Think you are looking at dbrown pics. I did bypass the relay. I just wonder if sport mode actually does open the flapper/damper when connected factory style to the relay. I never checked. One other thing I found while doing this is I thought the main batt. was under the spare tire tool/3D sub area. I have the 3D sub. My batt. is behind the backseat carpeted panel.
Last edited by wheatswake; Aug 14, 2023 at 12:37 PM.
Junior Member
Joined: Jan 2005
Posts: 60
Likes: 6
From: Palm City, Florida
2015 MB S550 Coupe, 2018 Carrera T, Ford F150
Cyberay,
Think you are looking at dbrown pics. I did bypass the relay. I just wonder if sport mode actually does open the flapper/damper when connected factory style to the relay. I never checked. One other thing I found while doing this is I thought the main batt. was under the spare tire tool/3D sub area. I have the 3D sub. My batt. is behind the backseat carpeted panel.
Think you are looking at dbrown pics. I did bypass the relay. I just wonder if sport mode actually does open the flapper/damper when connected factory style to the relay. I never checked. One other thing I found while doing this is I thought the main batt. was under the spare tire tool/3D sub area. I have the 3D sub. My batt. is behind the backseat carpeted panel.
Member
Joined: Apr 2016
Posts: 172
Likes: 45
From: Houston, TX
2017 S550 coupe, 2013 E550 coupe, 2008 Tahoe
So I have noticed after the car sits for more than 5 hrs the flaps go back closed, probably cause the valves on top of the muffler leak and do not maintain a vacuum. Hoping this will not be an issue. When I do start the car, they go open immediately.
Junior Member
Joined: Jan 2005
Posts: 60
Likes: 6
From: Palm City, Florida
2015 MB S550 Coupe, 2018 Carrera T, Ford F150
