New Exhaust Time

[PiercedE30]

Well, I have been slowly gathering parts for my new exhaust system over the past few months. There are a few reasons why I wanted to redo my exhaust. I knew that I wanted to get rid of the stupid 3 bolt flanges and gaskets, I wanted dual pipes, I wanted a larger muffler to aid in reducing volume and drone, and I wanted to use stainless steel. So, starting in October I began ordering parts. I was originally going to use two mufflers, one in the center section, and one at the rear. I ordered two mufflers from Jegs. One of them ended up being back ordered (as of 10/16/08), I still haven't received it and I canceled the order for it.
I ordered 4 4' lengths of 2.5" stainless steel (yes it is slightly bigger than most people would go for, but I wanted a deeper tone than I have right now which is almost ricey), 4 v-band kits for the flanges, one stainless steel O2 bung, 5 2.5" U-J mandrel bends, and the muffler that I chose is the DynoMax Ultra-Flo X muffler (part #17553). It is a straight through design with a X built in. I probably ordered more material than I potentially need, but I would rather have some left over than to have to stop half-way through a project and order parts and wait a week to get them.
I have had to borrow a SMALL argon bottle from a friend to TIG weld it all. It is a little 40 cf bottle. I have already had to have it filled twice and everything for the "cat-back" section is merely tacked in place. I will be going to the local welding supply and getting it refilled again tomorrow and hopefully I will be able to finish it up this section. I have the first V-band welded to a short length of pipe so that I can remove the 3 bolt flange from my existing "cat-back" section and be able to run the new rear section with the existing mid-section until I get that section built.
Enough with the details, here are some pictures:

Rear section:


V-Band and pipe tacked and ready to go onto the 3 bolt flange"


Muffler tip welds:



Muffler inlet:


Here are some videos of how my current system sounds:

http://www.youtube.com/watch?v=fx8N_zqvxmI

Go to 1:25 on this one:

http://www.youtube.com/watch?v=7FagT2hJHxg

My current system is dual 2.25" with an x-pipe right underneath the shifter to an E46 M3 resonator to a random DynoMax muffler that is about 6 inches shorter (length wise) than the new one.

[lowlightbw]

lookin good, keep it up

[e30_325es]

I can't wait to hear the finished product. I am planning that same muffler, but 2.25" and I'd like to place it right under the car where the cats were.

[jahnaboi]

Sad... do I see a tan cloth sport seat? Something I've been looking for forever...??!? Shame on you for dirtying it! Sell it to me.

Btw, nice setup. I wish I knew how to weld that good. Although I don't even have a tig welder... =/

[golde30]

how you gonna fit those tips through the valence!! interested to hear this setup, i need a new solution as well, mine sounds raspy and loud and drony.

[PiercedE30]

Actually, I had SERIOUS ground clearance issues with the V-bands and actually broke them off doing about 50 MPH. I got a new(ish) pair of 3 bolt flanges and put the old exhaust back on until I can get a bigger argon bottle and a chance to do the ENTIRE exhaust instead of trying to mangle a rear section just to fit to the hacked together front section.
I was using a 40 cf argon bottle and ended up having to get it filled about 5 or 6 times, twice in one day. But my god did it sound good. Honestly, I loved the way it sounded. It was MUCH quieter than my previous, and now current, exhaust due to the size of the muffler, alone. Oh, and the tips were just BARELY able to fit in the exhaust cut out. I am going to take a pair of short lengths and bring them inward (towards each other) by about 1.5 - 2.5 inches.
I don't think that this project will be done until I actually am able to pick up a daily driver and I can just park the car for a good week, week and a half to actually do the exhaust right without having to constantly stop and go have a bottle filled. I will probably pick up a 125 cf bottle, hopefully that will last a little longer.

[rbn14]

If you are going to upgrade bottles I would go to 155, its not much bigger that 125. What flowrate and postflow are you using? It sounds like they might be a little high, wasting some argon. Did you do anything to shield the backside of the welds (backgas or flux)?

[PiercedE30]

With my TIG torch:
I had the regulator set at about 12-14 cfh. No post flow control (I have a Lincoln DC stick/tig machine) other than pulling away from the metal to stop the arc and letting the gas flow over the metal until it cools enough to not glow red/orange. No back purging, no flux, decent fit up (considering I didn't have a pipe wrap to ensure perfect cuts with the Porta-band) with a c-clamp with a piece of angle welded to both ends of the c-clamp to hold the tube in place.

[rbn14]

Sounds like you got it all set up right guess I just dont have a good feel for how much (or little) 40cf of argon is. Does your TIG have a pulse function, they seem to work really nice for stainless. Were you able to get a good look at the back side of any of the welds? I have been told mixed things about welding stainless tube as far as shielding the back side of the weld. I just ask because I am getting ready to do my exhaust in a couple weeks.

[PiercedE30]

Actually, I would love to try putting some SolarFlux on the back side of the pipe. I was getting some sugaring if I didn't move fast enough (the damn thing down to about 30 amps). I was also using a #6 cup, 3/8's gas lens, 1/16 tungsten, and 1/16 304 filler.
In an ideal world, I would have a spare bottle/regulator to back purge everything. My machine doesn't have a pulse function, just straight DC power. I also have a cheapie Lincoln AC stick machine that I would like to try TIG'ing some aluminum with.

[rbn14]

For purging I just use a Y fitting where the gas line for the torch plugs in. I hook up a second line to it if I need to purge something. If that doesnt make sense I will try to snap some pics for you. I was thinking I would try out SolarFlux though since it seems to be less work and you would end up using a ton of gas. Burns Stainless makes it sound like they use SolarFlux and their stuff turns out great.
Aluminum isnt as hard as people make it sound, just make sure you get it SPOTLESS first or it is really frustrating, you just end up with two pools that bead and your pieces wont join.

[jahnaboi]

Pierced where are you located? Anywhere close to L.A.?

[PiercedE30]

PiercedE30
No R3VLimiter

Join Date: Apr 2005
Location: Baton Rouge, LA & Pascagoula, MS
Posts: 3,890
Images: 279

[jahnaboi]

Have you finished this by anychance yet?

[PiercedE30]

Nope. Been working 6 days a week 10 hours a day. I am only actually at the house for about 10-11 hours a day to sleep. But I have found out that one of my buddies from work has a big 225 CF argon bottle that I can use. The thing probably weighs over 500 pounds when full.