The complete muffler mount DIY info

[zactastic]

I combined all my research on this subject into one location.

The past month, I purchased a Supersprint performance muffler and after installation, I drove and motived one of my 19 year old muffler metal hangers fell out of the rubber mount, the other one isn’t looking good either. Ill post photos of my situation on that soon. Thankfully the muffler wasn’t damaged.

I ordered the new metal hanger (see parts below for part number) and realized I need new rubber mounts on both sides as the other has failed. While doing my research on this subject, I realized there are some debated options on the rubber mounts and re-enforcing them (if that’s really needed, you be the judge)

Here are some links to information that I hope helps someone else on this subject.

If you have a DIY for your supersprint muffler (or other aftermark mufflers) please let me know. The metal holder/brace (parts #9 and #10, realoem link below) that connects to the new muffler doesn't seem to sit correctly and im trying to figureout how to improve this so it doesn't fail in the future. (ill update my situation later)

Parts:
http://www.realoem.com/bmw/enUS/show...diagId=18_0215

Re-enforcing the mounts

DIY option to prevent saggy muffler mounts:
https://www.bimmerforums.com/forum/s...fler-for-cheap!

DIY to go from OEM rubber mounts to metal bracket type:
https://www.bimmerforums.com/forum/s...ust-Hanger-Fix

the napa version or Bosal mount:
https://www.bimmerforums.com/forum/s...exhaust+hanger

https://www.amazon.com/Bosal-255-070.../dp/B00180FTZM

Insert option:
http://www.revshift.com/product-p/pei-m3.htm
https://www.revshift.com/mobile/Prod...uctCode=PEI-M3

Forums and repeated debates on parts etc:
http://www.m3forum.net/m3forum/archi.../t-330838.html
http://www.m3forum.net/m3forum/archi.../t-340257.html

https://www.bimmerforums.com/forum/s...rs-much-better
http://www.bimmerforums.com/forum/sh...ts-from-the-UK

[zactastic]

I ended up ordering one Rein and one Genuine BMW mount to see if there is a difference in quality. Ive heard some say that the Rein has the metal insert but its covered in a thin layer of rubber. We will see.

The Bosal or CRP mount are similar to OEM BMW but some say the photos of the part may not be what you get so you should call directly.

I was going to purchase a CRP from amazon but I decided not to as i was order other items from ECS.

Here is the driver side mount and you can see that in the RED arrow the connection between the metal brace and rubber mount has failed, showing the white plastic internals. At first i saw this and didnt realized that this failed as it was nice and hidden, tucked backed and appeared solid on installation. well, i was wrong. The other side apparently had the same issue of which the failed first. Im use to a different hanger on the VW's but my lack of initial knowledge on these hangers was really low going into this. I suggests others look at all the parts they may need to buy before doing this job. I usually do, but this fooled me.
IMG_7579

The "Blue" line in the above photo shows the path of the metal rod thats welded to the muffler. I tried to draw the trajectory of the metal where it sits in the metal clamp. As you can see, it only goes in about half way. This next photo with the Green arrow shows that the this muffler rod isnt even visible as i believe it should be.
IMG_7581 ,
I may try to reverse the rubber mount so that the brace moves forward towards the front of the car, allowing more surface to clamp on the muffler rod.

[NeilM]

I've had a SuperSprint muffler on my M3 for years and years.

Yes, the mounting rods of the muffler are a bit short. You need to bias the rubber hangers toward the front of the car to keep the rod fully engaged while you tighten the clamp. It's one of those "and with your third hand" things. Once the clamps are tight it'll all stay in place.

I've also found it advantageous to put a large steel fender washer under the head of the bolt that goes through the center of the rubber X of each hanger. This spreads the lateral load and prevents the rubber from being pulled sideways out of alignment with its frame. This both extends the life of the hanger and makes it less difficult to keep the exhaust tips centered in the valance aperture.

The centering is determined by how you tighten the joints to the cat section. I shim the exhaust tips with a ½" socket drive extension rod on each side while doing that. Once the joints are tightened and the shims removed everything stays in place.

Neil

[jayjaya29]

I've had great success with the revshift inserts. They're on 4 e36m3s that I know of and they hold up great.

[Krohn27]

I'm also going to throw in the Hack Engineering billet muffler mounts in the mix. They are pricey, and people have opinions on the problems with more of a "solid" mount option, as it doesn't leave much room for vibration/expansion as things heat up.

That being said, mine are in the mail. I took off my original blown rubber hangers from my M3, and replaced with new aftermarket ones. A year later, they were already toast. The stock muffler is just so heavy, even nice OEM ones are bound sag. I'm going to install these and see how they do. Hopefully nothing cracks with the lack of movement back there.

http://www.hackengineering.co.uk/pro...ust-hanger-v2/

[JitteryJoe]

I'm also going to throw in the Hack Engineering billet muffler mounts in the mix. They are pricey, and people have opinions on the problems with more of a "solid" mount option, as it doesn't leave much room for vibration/expansion as things heat up.

That being said, mine are in the mail. I took off my original blown rubber hangers from my M3, and replaced with new aftermarket ones. A year later, they were already toast. The stock muffler is just so heavy, even nice OEM ones are bound sag. I'm going to install these and see how they do. Hopefully nothing cracks with the lack of movement back there.

http://www.hackengineering.co.uk/pro...ust-hanger-v2/

Let us know how they work out. Looks like a stout mount. I am curious about the lack of movement and whether or not that becomes a problem.

[NeilM]

I'm also going to throw in the Hack Engineering billet muffler mounts in the mix.

http://www.hackengineering.co.uk/pro...ust-hanger-v2/

Those look nicely made, but their poly bushings aren’t going to allow much movement, and seem rather over-engineered for what ought to be a simple job.

The nice thing about the SuperSprint cat-back, which is what the OP asked about and what I’m using also, is that it’s much lighter than stock. This takes a lot of load off the hangers. I’ve been using the same set of hangers for at least a decade – on a track car, where they take a pretty good pounding – and they’re still in fine shape.

Note that my trick with the fender washers, while relieving stress on the hanger rubber from excess lateral movement, still allows full vertical travel.

Neil

[zactastic]

Note that my trick with the fender washers, while relieving stress on the hanger rubber from excess lateral movement, still allows full vertical travel.
Neil

IMG_7625 by
I went with this on the back side of the hanger. I was already thinking about doing this. not sure if that's what you are referring to. This also prevent the bolt from pulling through and destroying the hanger and preventing it from falling off the vehicle.

- - - Updated - - -
IMG_7621 by [url=https://www.flickr.com/photos/76479274@N03/]

here is a side by side for comparison. The 44$ rubber is more flexible. The less expensive actaully feels more supported. As you can see, the metal is exposed on the more expensive one where as the rubber covers the metal internals on the cheap hanger.

- - - Updated - - -

http://www.hackengineering.co.uk/pro...ust-hanger-v2/

I believe these are discussed in one of the links i provided above. Look great, though there is that debate on being too supported leading to other issues along the exhaust.

[zactastic]

I've had a SuperSprint muffler on my M3 for years and years.

Yes, the mounting rods of the muffler are a bit short. You need to bias the rubber hangers toward the front of the car to keep the rod fully engaged while you tighten the clamp. It's one of those "and with your third hand" things. Once the clamps are tight it'll all stay in place.

Neil

Any issue on reversing the rubber hangers? It looks like in order to center and make the metal brace have good contact with the rods on my muffler, that ill need to switch the hangers. Ill try to take a photo as to what im talking about.

[NeilM]

IMG_7625 by
I went with this on the back side of the hanger. I was already thinking about doing this. not sure if that's what you are referring to. This also prevent the bolt from pulling through and destroying the hanger and preventing it from falling off the vehicle.

Yes, like that except that my washers are at least twice as large in diameter. (Sorry, no pix. Car is in winter storage.) The idea is to take lateral bending forces off the rubber arms where they join the hub.

Any issue on reversing the rubber hangers? It looks like in order to center and make the metal brace have good contact with the rods on my muffler, that ill need to switch the hangers. Ill try to take a photo as to what im talking about.

I see no problem with that. Do whatever works.

Neil

[zactastic]

here's what i was dealing with... the breakdown of a 17 year old hanger. strange how there is a white inner plastic piece. could this be some old design? it was ment to fail, just look at the looseness in the rubber around it.
IMG_7645 by [url=https://www.flickr.com/photos/76479274@N03/]
IMG_7646 by [url=https://www.flickr.com/photos/76479274@N03/]

[zactastic]

These photos compares the original position of the rubber hanger and how i reversed it to allow the metal brace to be more center on the muffler rod.

before position:
..see how the center of the rubber is off from the muffler rod.
IMG_7641

rotating the rubber 180 degrees you get this...

IMG_7643

this hanger position allows for better contact of the metal brace and it sits at 90degrees without any strange vector forces.

IMG_7644 by zactastic, on Flickr

Final placement of the passengers side hanger/brace:
IMG_7651
IMG_7650

[zactastic]

Here is the drivers side setup with the position changed 180 degrees like the passanger side.

top arrow shows some vector force causing some lateral movement inward about 1/4 inch.
bottom arrow shows the best contact i could get. It appears solid in the metal brace now. Ill post if there is any wear or break down on this rubber over time. i suspect this may cause the rubber to fail.

IMG_7652

- - - Updated - - -

The muffler tips sit correctly and ill post a photo of that soon.

I hope this helps someone or formulates more thoughts at least.

Cheers and happy new years!!!

[smason96]

Does anybody have advice on how to remove the rubber mount from the car? I took off the muffler, took off the metal hanger, and took off the nut that secures the rubber mount to the car but the mount will not budge. Do I just pull it straight down off of the bolts?

[Braymond141]

Does anybody have advice on how to remove the rubber mount from the car? I took off the muffler, took off the metal hanger, and took off the nut that secures the rubber mount to the car but the mount will not budge. Do I just pull it straight down off of the bolts?

Put your purse down and pull harder.

It works best if you pull at one side of the single mount which will release and lodge on the stud as it pulls down cockeyed. Push back into the body and pull down both sides of the single mount.

[smason96]

Put your purse down and pull harder.

It works best if you pull at one side of the single mount which will release and lodge on the stud as it pulls down cockeyed. Push back into the body and pull down both sides of the single mount.

Thank you for the levity and the advice. I was able to get it by pulling down very hard on just one side