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Subject: GUTTED MUFFLERS - LOTS OF PICS INSIDE (PART 1) Author: rhett : member since March, 2005 : 1455 posts Posted on: 2005-10-05 21:31:17

Now that I have your attention, I took my mufflers apart tonight. Since you have to pull the exhaust in order to get the transmission out, what better time to play a little with it.

The only tools I used for this were:
1) Safety Glasses - these are a must, a face shield would be nice too
2) 4-1/2" Die Grinder - 2 new grinding wheels
3) Large pry bar and hammer - you will see why
4) Sawzall with metal cutting blade

A little info before I get into the details. Our mufflers our whats called a laminated shell, meaning there are 2 layers - an inside and an outside. I started thinking it was only a single layer but then quickly realized it was a double. Its not that big of a deal when you do it my way.

Step 1) Lay your exhaust somewhere where all the grinding dust and sparks won't bother anything - mine happened to be in the driveway.


Step 2) Standing (or kneeling) over the top of the muffler, grind the top of the seam that runs all around the muffler


Step 3) Unbolt Factory hangers and grind the top half where it is welded to the top of the muffler. Sorry no pic of this one.... You want to seperate it from the shell though.

Step 4) When you were grinding, you should be able to make out the layers of metal in the grind marks, you might even get lucky and the muffler will start "popping" loose. Use the Pry Bar and hammer and work your way around making sure you get the top 2 layers.




Step 5) Now you should have the whole upper shell loose other than around the weld for the turndown. Grind the weld completely away from the turndown and the upper shell. You also need to grind the welds where the seams are. After this, pull on the shell from the front and work it up and down, grind where needed, and keep working it till it comes off.



Step 6) Take your trusty sawzall and cut the internals out. I left about 1-1/2" or so since I am going to try and get a straight thru tube made (that will be part 2).




Step 7) Stand back and think about what the hell your doing right now - but remember, its cheaper than a set of Dinan mufflers.


Should have more up this weekend, hopefully my parts come from Pacifc BMW, my tranny will be done tomorrow, so now I just have to pick up some gas for my welder and I am all set.

2000 740iL - 140k+ miles, stock other than 2 10" JL audio subs and big RockFord Fosgate amp :)
5% tint back 3 windows, supposed to be 30% on front doors (might be 20%)

• GUTTED MUFFLERS - LOTS OF PICS INSIDE (PART 1) (pic) - rhett 2005-10-05 21:31:17 (1389 views)
  • Holy crap that's awesome! - ArbysNight 2005-10-05 23:34:29 (147 views)
  • The force is strong in this one.............. (nt) - jfstu 2005-10-05 22:25:52 (100 views)
  • Wow man you are going all out. Did you ever replace your rear ball joints? (nt) - johngoga 2005-10-05 22:07:17 (133 views)
    • Nope, it ended up being the upper control arm was worn out - rhett 2005-10-06 07:44:16 (126 views)
  • Awsome write up.....what would the sound difference be between adding the - Tony K 2005-10-05 21:38:54 (127 views)
    • Re: Awsome write up.....what would the sound difference be between adding the - GER_545SMG 2005-10-06 00:47:45 (153 views)
    • Re: Awsome write up.....what would the sound difference be between adding the - rhett 2005-10-05 21:41:19 (185 views)
      • Re: Awsome write up.....what would the sound difference be between adding the - paul032562 2005-10-06 09:52:41 (133 views)
  • Here is a better pic of Step 2 (pic) - rhett 2005-10-05 21:36:53 (304 views)
    • rhett, thats great work A++, I wanted to do the same, but decided - itsstock 2005-10-05 22:12:17 (121 views)
      • Re: rhett, thats great work A++, I wanted to do the same, but decided - m5james 2005-10-07 12:17:59 (114 views)
      • I plan on posting a Video/Sound Clip after I am done - rhett 2005-10-06 07:43:04 (130 views)
      • WOW!!! That's cool Rhett, Hope it works the way you want it to perform (nt) - HighLine740iL 2005-10-05 23:50:55 (109 views)