Hi everyone, I have a 2009 ML550 with a standard exhaust which is very very quiet. I've read ALL the posts here and elsewhere and although helpful, raise as many questions as they answer. I'm looking to get more sound, but no drone. Can anyone advise if I replace the rear mufflers with some magnaflow items (or similar) but retain the centre resonator (I'm worried that if I remove them I'll get drone impact) what the uplift in sound might be? I've seen people replace the resonators with magnaflows and then straightpipe to the tips including but am worried that will be too loud.

I want to retain the relative silence at cruising speeds (some rumble is ok). Exhaust shops give such varied advice and anyone whose experience with keeping and or removing the middle mount resonators would be much appreciated. A 30-40% uplift in sound is what I'm looking for, even more when you gas it (if possible) but relative quiet at highway speeds. Possible I'm asking too much.

I've attached a photo of what I've got below. The resonators are large so my concern surrounding drone comes somewhat from that. Thanks again to all and anyone who can assist with their experiences. Anyone with part numbers for their magnaflow exhuast would be great.

Centre Resonstors

 

Resonators control drone. https://itstillruns.com/function-muffler-7474991.html
Keep scrolling down on the link I posted, it covers other components in the exhaust system.

If you want to control your exhaust sound from mild to wild, without having to experiment with j pipes and resonators, cut out's would be my choice.

Helmholtz resonator & J pipe

 

many thanks for the videos. they are very informative. i never knew that you could measure sound with such a simple app. I'm going to do this over the weekend and see where its at right now before i make any changes. It will be interesting to see any before and after differences. I appreciate the time you've taken to respond.

 

I removed my resonators and kept the stock mufflers. At idle and low throttle the sound difference is negligible.

At startup there is a deeper tone.

At WOT I would say your looking at a 20% increase in sound. Deeper.

No droning at all.

Here is a vid.

 

The best option for upgrading the ML550 exhaust is to get your hands on a used ML63 exhaust - you'll need the center resonator, and the L & R rear mufflers (with the quad tips). You'll have to swap out a couple of the rear exhaust hangers, and to do it completely right, also replace the lower rear valence panel with one that has the opening for the factory quad tips. Once completed, it looks completely factory installed. An upgraded exhaust should have been an option from the factory! The performance increase after doing this is immediately noticeable due to the larger, mandrel bent piping of the ML63 system. It lets the M273 engine actually breathe. The stock ML550 exhaust, in addition to its restrictive smaller pipe diameter, also has some very restrictive areas where the piping has been crimped severely enough to restrict flow. End result for me was an amazing performance increase combined with a perfect exhaust note - not too load, no drone, but aggressive enough to suggest the beastly V8 lurking under the hood.

 

Haha many thanks. That sounds great. The fact you had no drone is consistent with what I'd been told but I'd never heard it directly from someone whose actually done it. So, I did the same yesterday and got exactly the same outcome. Deeper sound on start-up (and louder as it warms up), pretty much the same at idle (maybe +10%) but a great raspy sound on full throttle. No drone at all at local or highway speeds or under load. I can now hear the V8 burble which I couldn't before, just loud enough in the cabin so you know it's there. I haven't yet heard it reflecting off some walls whilst out on the road, but it sounds pretty good. We simply cut out the resonators at the existing join, welded in two new pipes with the supports and off I went.

I must say say removing the resonators went against my instinct but I think this was exactly the right way to go for the impact I wanted and at a very reasonable cost. I'd suspect if I want it louder that I'll do the mufflers next time which may require putting the resonators back in but we've kept them so that shouldn't be an issue. Many thanks for your response and video. Helped me a lot.

For the benefit of others I've posted before and after photos.

 

Haha many thanks. That sounds great. The fact you had no drone is consistent with what I'd been told but I'd never heard it directly from someone whose actually done it. So, I did the same yesterday and got exactly the same outcome. Deeper sound on start-up (and louder as it warms up), pretty much the same at idle (maybe +10%) but a great raspy sound on full throttle. No drone at all at local or highway speeds or under load. I can now hear the V8 burble which I couldn't before, just loud enough in the cabin so you know it's there. I haven't yet heard it reflecting off some walls whilst out on the road, but it sounds pretty good. We simply cut out the resonators at the existing join, welded in two new pipes with the supports and off I went.

I must say say removing the resonators went against my instinct but I think this was exactly the right way to go for the impact I wanted and at a very reasonable cost. I'd suspect if I want it louder that I'll do the mufflers next time which may require putting the resonators back in but we've kept them so that shouldn't be an issue. Many thanks for your response and video. Helped me a lot.