I did a search and to my knowledge this hasn't been covered, so I'll give it a shot.

Ever since I got my Civic I had my OBX exhaust. It was kinda loud and people hated my car. I realized that it was kind of unnecessary for a car to be loud in town. I had this crazy idea that I could make a thing that would allow my mufflers be interchangeable, so that on a whim, within 5 minutes I could swap a quiet one for a loud one, for instance if I were to go racing.

Most dismissed my idea as "stupid".

A few weeks ago, my friend Nelsmar decided that he really wanted to take off on my little idea and do the interchangeable mufflers. He bought the flanges, getting raped at a muffler shop into paying $30 for 3 pieces of metal. He then went to the Checkers and got a $25 muffler. I did the welding along with a friend of ours who did the finishing-up, and it actually worked out really well. The car was alot more civil to drive around town, and got the cops off of his back.

So, I decided I was going to go for it.

First off, I needed the flanges. I didn't want to get raped, so I went to the scrap metal bin at my work and got a piece of sheet metal that was 3ft by 3ft, and cut out some equal length metal pieces to get started with. We have a full service machine shop and the guys there are into cars so basically I get to do whatever I want.

I measured the exhaust, finding that it was 2.5". I also decided that I wanted the exhaust to look kinda stock-ish, so I would have it go sideways under the car.

Pic of the metal pieces on the vice on the drill press, awaiting the 2.5" center hole.



After I got that drilled out and all, I bought the muffler and 2.5" > 1.75" adapter from Checkers. Total cost: $32.

Pic of the New Checkers muffler



I was hesitant about hacking up my poor exhaust, but my boss was just like "DO IT!!!" So I took the plunge and using the Port-a-Band, went *HACK*



It looked fairly easy from here. My flanges fit up really well, and I was excited.

The next part was to fit the flange onto my existing piping. You can see where I did it on the pic with the new muffler, up in the top of the picture. Pictured is the flange with the adapter. Since the differences in the thickness of both metals was great, I had my boss weld the flange to the Checkers adapter using spot-welding, as I was not very good at that technique yet.

Next step was to weld the muffler to the adapter. I wish I had more pics but I was in a hurry because we had to close up soon. Anyways, me getting ready to weld the muffler to the adapter and the flange to my exhaust piping:



Now with that done, we move onto the old muffler. I test fit the flange to it and weld:



Now I wire wheel all my welds, and call it a day:



(edit: ^^^^^not trying to look like hardass, just unable to take good pics of myself)

Next to come but had to be postponed due to lack of time are more user-friendly muffler mounts and some gasket maker for the seal. The car sounds SOO quiet now, more people want to ride with me, and my head hurts less. Highway is much more fun now, as is hearing my new ebay intake .

So, there ya go. 2 days and $32.

I never got a pic off of the finished product before I went back to college, so I'll have a friend stop by and snap a few sometime.

Discuss?


Modified by 31flavorscivic at 11:31 PM 1/23/2006


Modified by 31flavorscivic at 12:24 AM 8/8/2006

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by rotaryman &raquo;</TD></TR><TR><TD CLASS="quote">No more fartcan you should paint that muffler black and weld on a stockish looking tip</TD></TR></TABLE>

I was going to go and get a 90 bend and a $10 tip from Checkers, but ran out of time before I left. Lol it was kinda funny having the exhaust coming out of my rear left tire for a while. People said it looked like my brakes were on fire.

But yea, thats the plan. Cuurently car is parked for a while, as I am 300 miles away, but it is on the to-do list.


Modified by 31flavorscivic at 12:27 AM 8/8/2006

 

project is done, took me about 5 hours to get everything working just how I wanted it to.

first thing on the list to do was to make my exhaust legal by coming out the back of the car.

borrowed my friend's welder to finish the job, since I no longer work at the place I started the project at.



I welded a 90 degree on there that I bought from Checker auto parts for about $5.



I had a tip to weld on there to make it look decent, but it sadly perished when I absent mindedly placed it right next to where I was welding.



So, I just went back out and bought another one.



Those tips are meant to go onto exhausts with like 1-3/4" pipes, so I had to yank the mounting hardware out and weld the tip directly to the pipe. I put an old sock over it to make sure that it didn't suffer the same fate as the last tip.



Finished product (almost)



My goal was to make this a completely sealed system, with absolutely no leaks, so I went and bought Gasket Maker type 1 from Checker's. I spot welded around the tip and sealed that, then sealed around the 90 degree. The other welds were done fairly well and didn't need them. It's not like I am an expert welder or anything, so this definitely helped.



Finished and mounted on car:



Now with the important stuff done, I could concentrate on the obx muffler. I started work on that, welding the flange to it first (my welds are slowly getting better):



completed:



mounted on car:



The two mufflers sitting side by side:



I seal both mufflers with high temperature gasket maker type two (the non-hardening stuff) between the gaskets, and it makes a perfect seal.

I am glad that I did this project. It made the 4.5 hour ride to college a LOT less painful than similar rides in the past. I could actually hear my music and hold conversations with people in the car. By far the best modification I have ever done.

It also allows me to scoot around town quietly, and that was important back where I used to live because the police would look for easy targets to pull over, just to make it look like they were doing their job. This allows me to kinda fly under their radar and avoid being harassed.

It takes about 6-7 minutes to switch the mufflers out. I chose to not make a mounting bracket for the OBX because it was time consuming and began to complicate my design, and I chose to hang it up by the largest hose clamp that Home Depot had. I had held it up by one of those back when my muffler fell off, and it makes for a really convenient mount, especially because it is just temporary. The quiet one is held on by a bolt passing through two rods, one connected to the muffler and one to the car. Removal is quite simple.

 

a little more expensive but less time comsuming idea is v-bands. 1 bolt instead of what looksl ike to be 4 on yours.

 

hmmmm i like the idea and have access to that stuff at home. once im boosted that would be a great thing to have. ricer muffler for showing off...quiet for cruising.

 

I dont quit like the way your stock exhaust is mounted. Its a little off if you ask me. If I were you I would just buy a not so noisey exhaust that still performs good so that you dont have to go through this nosense. Ask yourself is this really worth it?? There are several good exhausts that are not loud but still perform good. Your best bet would be to do that and then make yourself a dump vavle for race time.

 

I like your idea, in fact, I used to use a turn-down pipe bolted onto the stock muffler flange when I'd autocross.

My question is why did you do it with flanges, instead of coupling "collars"? I've seen such coupling pipes for $5 at autoparts stores in a variety of diameters, and you can cut a slit in them and use a clamp or screw to hold them on very tightly.

I've considered putting a coupled section on my Greddy SP2 just to make the back section easier to remove.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by nicks_jdmstyle_ef9 &raquo;</TD></TR><TR><TD CLASS="quote">I dont quit like the way your stock exhaust is mounted. Its a little off if you ask me. If I were you I would just buy a not so noisey exhaust that still performs good so that you dont have to go through this nosense. Ask yourself is this really worth it?? There are several good exhausts that are not loud but still perform good. Your best bet would be to do that and then make yourself a dump vavle for race time.</TD></TR></TABLE>

Many owners ago, they did something really weird with the piping. This is a pic of when I first bought the car, the piping bends down in a weird way:



That's why it doesn't sit quite right. I wasn't happy about that, but what came out wasn't too bad.

People said I should weld on a V with an electronic valve, but I chose to go this route. This only cost me a total of about $45 in parts. I already had the 2.5" piping from the cat back, so replacing the exhaust wouldn't have been a cost effective alternative. I wasn't prepared to try out a ton of exhausts to find out which one was quiet either.

I also wanted total silence on the highway. I had to travel 4.5 hours this time, and didn't want a repeat of race season, when I was making 4 hour trips to the track and got to enjoy the rest of the weekend with a massive headache. No performance exhaust will give you more or less total silence. My transmission is so short that I am at 4500 RPM going 85 on the highway. It's a pain to have a performance exhaust then.

Performance isn't affected too bad, because there isn't a horrible reduction in flow. It does make a little noise when you open it up, but the intake drowns it out at high rpm.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dseries_ef &raquo;</TD></TR><TR><TD CLASS="quote">hmmmm i like the idea and have access to that stuff at home. once im boosted that would be a great thing to have. ricer muffler for showing off...quiet for cruising. </TD></TR></TABLE>

total of 5 bolts. I love it.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by UltimX &raquo;</TD></TR><TR><TD CLASS="quote">a little more expensive but less time comsuming idea is v-bands. 1 bolt instead of what looksl ike to be 4 on yours.</TD></TR></TABLE>

I don't know what these V bands are that you are talking about? Sound interesting though. We tried this idea on my friend's crx first, and he got ripped by a shop into paying $30 for just the 3 flanges, then he had to buy the additional $30 in parts. I had some extra scrap metal at work, so I chose to make my own for free.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by fireant &raquo;</TD></TR><TR><TD CLASS="quote">

My question is why did you do it with flanges, instead of coupling "collars"? I've seen such coupling pipes for $5 at autoparts stores in a variety of diameters, and you can cut a slit in them and use a clamp or screw to hold them on very tightly.</TD></TR></TABLE>

That was my original idea, but I rushed it and didn't really know where to find the parts. You're talking about something like how the downpipe goes into the cat, correct?

If I had to do it over again I would do it that way. I just didn't put that much thought into finding that.

 

Here's what I mean...



It's really up to finding the right inner diameter of pipe for the coupling, and finding a straight section to work in. I did this exact thing when I sawed off the huge tip on my Greddy and put on a turndown in its place.



turns out that 2.5" pipe is a great fit for coupling 60mm pipe.

 

ah, that looks like a good idea. Would have been alot easier than what I had to go thru, as that doesn't really require much if any welding. Everyone should post up their thoughts/ ideas on the easiest way to do stuff like this; as this is what I wanted the thread to be about.

I was majorly hindered by not having a straight section to work in. I had to cut it off right after that unnatural downward bend, and it made my exhaust go too far to the left, so I had to move things around to make it look alright, but if you sit and examine it for too long starts to look pretty weird.

All in all, I am happy with the outcome. I don't plan on changing it anytime soon, as it is functional. I had to rush this because it was spring break and I had to get it done before I was to go on the highway back to school. I'm away from all my tools and everything, so I had to finish alot of crap on the to do list before I left.

 

forgot to put up a pic of the finished product:

 

Turn down looks sick!

 

would of looked a million times better if you made it dual...looks like you could fit 1 more pipe right next to it.

 

dont mind the crappy welds, no leaks. It's a borla with dual muffler with rsx tips. Very Mugen-ishy

 

Im in the process of making a custom exhaust for mine. its a full 2.5" exhaust, with a dual tip magnaflow muffler, its real quiet when im crusing, but it does provide a source of restriction. so what im doing is getting an e-cutout (either electronic or switch/lever operated.) and welding that in palce of my cat, or right before the cat, but that would require alot mroe welding.

so its nice and good looking, but flick a switch and VROOM open headers for race weekend