[avocet]

Yes, I agree thw stock muffler is ridiculous. But I am using this as a stop gap measure. But, since actually doing it, I have found the results very good!

I just might keep the modded muffler for awhile!

[ZeroSum]

Originally Posted by TheAxiom

Or....a Borla XS muffler is 100 bucks welded at a shop, ia lighter and can free up some power.

This

[armansiu]

I am cutting all the pipes inside and just connect the inlet to the outlet inside the muffler box with some straight pipes.
My friend is doing this project for me, hope this will be done soon.

[howardx]

Originally Posted by avocet

Well, for anyone interested, I gutted my oem muffler. I cut out all the pipes but still used the baffled sections and left all the packing in there.



The red lines is where I cut. i just used a sawzall with a metal cutting blade. It cut through like a hot knife in butter!!! lol.

After the first start, it was very quiet, to the point of me thinking it was a waste of time. But after a few weeks it started to get a little bit of throat and is now quite nice! I am very tempted to leave it as is.

Because it was so quiet, I had gone and grabbed a second oem muffler for 20$ off craigslist and am planning a second attempt at doing this to make it a little bit more... ahem, sporty. By leaving in the pipe marked yellow, the exhaust path will go through the baffles only once directly from entering the muffler, then straight out the exhaust. My current set up has all the exhaust gases going though the baffled area though 5 different ports. It should make it alot less muffled and should still utilize the open area of the muffler for resonance suppression. ie drone.




My aa gen 1 exhaust with the aa headers was simply ignorant loud and had miserable levels of drone. I had a spiral sound baffle in there, but it droned like hell with the header. I took it out and the drone actually was reduced, but it became hella loud.

Since this other muffler is only 20$ I will be doing this mod in the near future and will post my results! It won't be for a few weeks though, because I have a very busy summer ahead of me...


P.S. Thank you OP(howardx) since I used your pic and used paint to mod it!!!



P.S.S. I will also say this thing simply pulls harder through the midrange with the aa exhaust removed and the modded muffler in place. No placebo. It pulls harder.

This is revolutionary. Can I get a quick phone video of what your current mod sounds like? I want to decide to gut all pipes or keep the inlet pipe. And also, do you still have AA headers on? That would be a factor in your exhaust sound.

Thank you for your find avocet!

[avocet]

Originally Posted by howardx

This is revolutionary. Can I get a quick phone video of what your current mod sounds like? I want to decide to gut all pipes or keep the inlet pipe. And also, do you still have AA headers on? That would be a factor in your exhaust sound.

Thank you for your find avocet!

Ya I wil try and get a video sounder clip this weekend. I am out of town right now but should be home ob the weekend.
And yes, I am still running the header.

I had my old muffler hanging around for ages with the intent of modified it. Your original post finally gave me the motivation to do it. Thanks!!!

[howardx]

avocet Have you gotten around to taking a quick sound clip? I am looking forward to hearing it and starting my mod this week!

[avocet]

Ah crap no I didn't have time. Was only home for 2 days and am back out of town...
I didn't even start my Bimmer! Being a holiday weekend I went home to go away for the weekend! Lol.
Happy belated Canada Day and Independence Day!

[08njSTEP]

I am surprised nobody has tried running a Supertrapp. Straight through and tunable(add discs makes louder). Stainless model runs about $100.

[E91 M Sport]

Originally Posted by 08njSTEP

I am surprised nobody has tried running a Supertrapp. Straight through and tunable(add discs makes louder). Stainless model runs about $100.

Sorry man but those things don't belong on a German car.

[08njSTEP]

Calloway used them on his Sledgehammer corvette that did 254mph. Tucked back underneath bumper wouldn't even be noticed.

[E91 M Sport]

Originally Posted by 08njSTEP

Calloway used them on his Sledgehammer corvette that did 254mph. Tucked back underneath bumper wouldn't even be noticed.

That vette is/was no joke (and would probably run awesome with water melons as mufflers) but that was in the 80's bud. Dare I say the 80's called and want their muffler (technology) back?

[avocet]

Ok here is a link to the youtube video I posted... it is a crappy phone vid taken in a dark undergoing but hey...

It sounds like crap on my phone but ok with my stereo. So, after some technical youtube challenges here is it:

[howardx]

Originally Posted by avocet

Ok here is a link to the youtube video I posted... it is a crappy phone vid taken in a dark undergoing but hey...

It sounds like crap on my phone but ok with my stereo. So, after some technical youtube challenges here is it:

Thanks so much for the vid! Now I have an idea on where to start.

[mason_paul]

Ok, so I have a muffler and resonator assembly I bought through eBay. The question I have is, where do I cut the pipe between resonator and muffler? There aren't any circular sections, it's all flats and complex curves. Did you use a clamp or just weld the pipes back together when you reinstalled? Thanks!

I have an E91 I'm trying to avoid dropping the rear triangular subframe in...but otherwise stock exhaust (no headers). I think I'll try your second plan first, post a clip, and try the fully empty option second if needed...

[avocet]

I cut mine about 4" forward of the muffler. As soon as it bends down there is a short straight section(on my e90) that is enough to use a coupler and 2 clamps.
Try to find an AA gen 1 exhaust DIY and cut in the same place(I had an AA before I reinstalled my oem muffler)

My original pipe was about 1-1 1/2" longer than this install... it wasn't welded and was long enough to slip a joint over:

http://www.e90post.com/forums/showthread.php?t=749418

Originally Posted by mason_paul

Ok, so I have a muffler and resonator assembly I bought through eBay. The question I have is, where do I cut the pipe between resonator and muffler? There aren't any circular sections, it's all flats and complex curves. Did you use a clamp or just weld the pipes back together when you reinstalled? Thanks!

I have an E91 I'm trying to avoid dropping the rear triangular subframe in...but otherwise stock exhaust (no headers). I think I'll try your second plan first, post a clip, and try the fully empty option second if needed...

[David0ff]

This thread is about that, read the posts above.
But the operation is resume as such:
Cut muffler from car
Place on floor
Take a grinder and open it up like a can of tuna
Take same grinder and perform operation delete on anything in the muffler that you want.
Once satisfied with operation delete weld back the muffler carcass
Re weld to car
Drive around for 1 hour before you realize you hate yourself for wasting a saturday
Look on forums for OEM muffler
Buy Oem Muffler
Swap back on car
Have beers and sex

[Ruddigger]

Hahaha.

[justpete]

Originally Posted by David0ff

This thread is about that, read the posts above.
But the operation is resume as such:
Cut muffler from car
Place on floor
Take a grinder and open it up like a can of tuna
Take same grinder and perform operation delete on anything in the muffler that you want.
Once satisfied with operation delete weld back the muffler carcass
Re weld to car
Drive around for 1 hour before you realize you hate yourself for wasting a saturday
Look on forums for OEM muffler
Buy Oem Muffler
Swap back on car
Have beers and sex

This belongs in the DIY section.

[roccy_miyagi]

so i'm guessing nothing good came of this lol

[avocet]

Originally Posted by roccy_miyagi

so i'm guessing nothing good came of this lol

Nah is all good! Still have my original modded muffler on and it sounds great! Yes a little more volume would be nice..

I simply haven't had time to attempt the second muffler. I pretty much work all summer away from home and right now it looks like I'll be away most of the winter too!

Not too sure why people trash muffler mods so much. People using ducting to increase airflow to brakes and home made CAI's don't seem to get the flack

At the end of the day it is all about execution. I tend to do things properly, I enjoy tinkering and if it doesn't work out I usually dig in and make it work rather than scrapping it. Lol. Guess I am stubborn that way.

[roccy_miyagi]

Originally Posted by avocet

Nah is all good! Still have my original modded muffler on and it sounds great! Yes a little more volume would be nice..

I simply haven't had time to attempt the second muffler. I pretty much work all summer away from home and right now it looks like I'll be away most of the winter too!

Not too sure why people trash muffler mods so much. People using ducting to increase airflow to brakes and home made CAI's don't seem to get the flack

At the end of the day it is all about execution. I tend to do things properly, I enjoy tinkering and if it doesn't work out I usually dig in and make it work rather than scrapping it. Lol. Guess I am stubborn that way.

i can agree with you there.... i just landed a job at a bmw dealership, so i can def see if can i get my hands on a PE & cut it open to see exactly whats what. I'll do it for the culture lol

[tdavis42]

Originally Posted by roccy_miyagi

i can agree with you there.... i just landed a job at a bmw dealership, so i can def see if can i get my hands on a PE & cut it open to see exactly whats what. I'll do it for the culture lol

Before you cut it open you should send it to me for testing.