Uda880

Hey everyone, I thought I would at least document this since I've been scouring the BMW/Mercedes, and even the Chevy/Ford forums for some answers.

Car information:

• Model: E550
• Year: 2010
• Engine: M273 N/A

1. Resonator Delete:Like everyone else, I started off my exhaust journey by doing a resonator delete. While looking for a more raw sound, I chose to go with straight pipes instead of an X- or H- pipe because I wanted a lot more volume without having to change my mufflers. Once it was replaced, it sounded decent, with a nice burbling and rasp on deceleration, while the WOT sound was aggressive and raw, and with the stock exhaust tips, it provided a trumpet effect, making the exhaust noise at WOT only louder. The only downside to this was that the idle resembled a slow exhaust leak, or even tractor like, with a light putt-putt. Little did I know, the pops, and the raw sound of the straight pipes were because the engine was running less efficiently without the scavenging effect of an X-pipe, and it actually affected MPG (lower) and drivability (introduced a lag when pressing on the gas pedal to when the engine responded. There were several times on the freeway during passing, that the engine lugged and failed to speed up until 4 seconds later - when the transmission downshifted).
   
   
   1. Sound Loudness: 5/10
   2. Drone: 0/10
   3. NVH: 1/10
   
   
   2010 E550 M273 E550 V8 NA, Resonator Delete - YouTube
   Night Drive - YouTube
   
   
2. Magnaflow Mufflers with Straight Pipe Resonator Delete: Here's where it gets a little more interesting. I wanted more sound, I wanted loud, and I also wanted to get rid of the BRAAAAAAAT noise, so I went to my local muffler shop to have my stock mufflers cut out and had Magnaflow (model #11226) placed in. These being 14" diagonal mufflers were a great fit in the stock muffler positions with some slight angles. These were combined with some dual tips to finish them off. Now, Magnaflows are known for there slight, bassy drone, and combined with the straight piped resonator delete, the noise was VERY bass filled, so much so that even during regular acceleration, you can hear and feel the bass in the cabin. There was also droning during the usual 1500 - 1800 RPM range, but the external sound was fantastic, loud, and muscle car like; and with the Magnaflow mufflers, throttle response was back to normal and the car felt like it had more pickup throughout the RPM range.
   
   
   1. Sound Loudness: 9/10
   2. Drone: 6/10
   3. NVH: 6/10
   4. iPhone DB measurements: Peak @ 96, average around 89 db
   
   
3. Magnaflow Mufflers with Stock Resonator: So I decided that I can't stand the drone, and after much research, decided to place my stock resonators back on. That was interesting as well, as it changed the tone to become more high pitched, it eliminated most of the bass, and completely shut down any exhaust noise! The cabin became dead quiet, and even when I had the windows down, I simply cannot hear any exhaust noise from the V8! Felt like I was driving a hybrid at moments. Although, after recording the noise with my GoPro and external mic setup, I've realized that it began to sound more and more like the exhaust noise from a VQ35DE - as in G35 and 350Zs.
   
   
   1. Sound Loudness: 2/10
   2. Drone: 2/10
   3. NVH: 1/10
   4. iPhone DB measurements: Peak @ 81, average around 76 db.
   
   
   I made my V8 Mercedes sound like a G35 - YouTube
   
   
4. Magnaflow Mufflers with X-Pipe: So here is where I am today. I decided that I wanted more sound, but also didn't want the lumpy, drone filled performance of the H or Straight pipe. I went ahead and had the muffler shop install an X-Pipe in place of the stock resonator. Keep in mind that the X-pipe itself was installed towards the front of the resonator gap, with stainless steel 2.25" tubing extending towards the aft section, that leads to the Magnaflow mufflers. Now I have great performance, more volume than the resonator combination, but most of all, NVH is down and the sound of the V8 is very harmonious. Very little drone inside (some around 1500 - 1800 as expected, but better than straight piped), and you can pleasantly hear the engine both inside and out. This is really the Goldilocks of the combinations, and I can't be more satisfied. Video to come soon!
   
   
   1. Sound Loudness: 7/10
   2. Drone: 3/10
   3. NVH: 2/10
   4. iPhone DB measurements: Peak @ 89, average around 85 db.

ffr2014

Great review! I did the resonator delete with straight pipes on the M278 (TT-V8) so experienced none of the performance degradation or MPG decrease due to turbos. No drone and only slight tractor like sound at idle and only from outside and standing behind car. Still love the increased sound on heavy acceleration.

2010_E550

Not sure why you would want your car to sound like a G35 or a 370Z... I guess Ill take your word for it, but all I hear in those videos are farts and air noises.

Uda880

Update: Went back to straight pipes. The sound with the X-pipe was too soft, high pitched, and made the car sound like a V6. Straight pipes definitely gave the exhaust more character, growl, and I learned that I enjoyed a bubbly, uneven exhaust sound.

bill_097

so, you mean it now sounds like the second video?

ob2s

Now after 4 mods, would you have stuck with the OE setup knowing what you know ? Is the #2/#4 setup back to normal MPG ?

nsb_88

Pseudomaniac

The NA car and M278 car are completely different animals though. You've got two small turbos eating the exhaust pressure to consider in both terms of performance, and sound.

I just purchased a '14 E550 Cabrio for a summer car. I had the Renntech mufflers on my M278 CLS550, and while they were a little gurglier, they were far from loud. No drone. A little more throaty. Ridiculously expensive for the sound difference, but dyno showed they did open up 12-15hp across the powerband.

I had a 13 C63 AMG, and received countless compliments on the exhaust and sound of the car (stock). It pounded the floor in the garage.

I know the M278 isn't going to have that rumble to it without drone, being a boosted, small displacement V8, but I'd like to get some more of that bass to shine through at WOT.

Am I correct in saying, your experience with just the Magnaflows is that the sound is actually quieter?