Single side exhaust...
 

I have had a few inquires about my single exhaust so here is the info: Built it myself, borrowed a small portable wire feed welder, cut some bends and went to work. As you look at the pics be nice, I am not a great welder. It is possible that you could do this system with clamps if you do not have a welder, but you would most likely have some leaks as clamps never seal that good.

pics: http://www.cactus.org/~edj/rx8club/muffler/

I cut off the stock muffler about 6" down from the slip fit at the muffler. Then used the U bend to make a large curve, around 110', into the muffler the other end slips over the stock cat-back pipe. I have the muffler tilted up slightly as it goes from the center of the car out. Then cut the J bend at 90' to make your exit. Keep in mind you need to make the exit long enough that it clears the plastic area of the bumper. With the single exhaust there is A LOT of heat coming out of that one pipe and you can melt the plastic if you are not centered in the opening or you make it to short. For a tip I just cut the end of the pipe at about 30' and painted it black with high temp paint. For a hanger I used a piece of 5/16" round bar from Lowes. I bent a 90' on each end, making a squared off U shape, so that it would line up with the factory hangers on the passengers side then welded it to the top of my outlet pipe.
I do not have any HP/Tq info on this system. Due to the lack of credible dyno numbers, damn ECUs, I did not bother with dyno runs. I figured it was not important to worry about a few HP, as most after market systems make 2-3hp, I just look at it as saving 22lbs.
I do not have a DB reading. I can tell you at the San Diego Natl tour they were monitoring Dbs and I was no where near the 93db limit. There is another RX8 in SD with a single side system using the 12" long XR-1 and it has hit 93db once, may have been a fluke as it usually is under, and my car is significantly quieter. I know a few members were in SD and may have heard the system and could comment. Also while in AZ I had a couple of members ride in the car at an autoX and they might have sound/volume feedback as well.

All of my parts came from Summit Racing: All parts are 2 1/2" diameter.

Borla XR-1 16" long: PN# BOR-40942 $132.95
Summit U bend: PN# SUM-622003 $16.95
Summit J bend: PN# SUM-621008 $16.95

Sounds like my cue. The sound reminds me of a first gen with the racing beat street port exhaust, very distinctive, but not quite as deep. Sounds good to me, but I grew up driving a 12A with a header and the stock muffler, so I may have a different view (ear) on things. The car in SD with the 12" Borla sounded the same to me, just louder. Kind of what you expect from a smaller muffler. I didn't think either were annoying, but the 12" on a road trip might get old, at least from what I heard from outside the car. Bottom line from me: Sounded Good, I plan on doing it myself once I get off my lazy bum. I just wish that the car would do the wicked bad rotary fart/burp/ball o' flame.

ChopsMcgraw

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Even though there may or may not be big power gains, how does it feel? does it feel any faster or is it honestly too hard to tell?

The link ULLLOSE lists above should now work. I didn't get a chance to add the
pictures until this morning. Sorry about that, Chief.

The big question I have is how does the car sound driving on the highway? I
presume it is louder than stock but how does it sound inside?
Does it get annoying/painful after a few hours?

Neither car sounded very loud from where I was watching during your heat (the corner of the paddock that kind of jutted into the course area next to the grid). Now that I think about it, though, I can't really remember much else about it.

edit- And thanks for the info, too. :o

Very mellow on the road, you can tell it is not stock, but it wont drive you crazy.

You can not tell. Anyone that puts on a cat back, air filter or does a ECU reflash and says they feel it is full of $hit.

For reference, on my vette we built a similar exhaust, 12" XR1 single side 3" pipe. It gained 4hp and 18tq at the wheels, you could not feel that at all.

Your butt dyno is not a good tool. :D

Think about the fact that your RX8 weighs around 2900 lbs.... Has 238 crank Hp, yeah right Mazda, and if you pick up 2hp with a muffler change that is less than a 1% change in power. NEVER EVER GOING TO FEEL IT. You would see more of a change if you ran your car with a full fuel thank and then ran it with a 1/4 tank. :cool:

Me too..... I was so bummed it does not do that. Maybe if we take of the resonator and cat. :D

Andy Mckee's SM2 RX7tt shoots out about 4' of flames. :cool:

Any thoughts on having the single exhaust coming out of the center? Maybe through the rear rotor symbol?

I did think of that, would look sweet. However not solo2 stock class legal as it would require us to cut a hole where there was none.
Also for racing in stock class we can not corner weight this car, no factory adjustments. However what we can do it put the muffler in the corner where you need extra weight, pass rear, this helps to offset the drivers weight on the left side of the car. ;)

For local events (where we're allowed to do it), SoloII///M has taken a different approach to that question and the right side still won't stay down. ;)

http://vorlon.cwru.edu/~jpv/M3/lifti...ed_resized.jpg

damn your front wheel is off the ground, thats some hard suspension and cornering there :)

More like soft suspension, sticky R compound tires, and a front sway bar.

Koni DAs but OEM front bar

The weight in the rear is to keep the back tire down, you need it that way to put power down, its all good if the front is up. :D

whatchatalkinaboutwillis :confused: :rolleyes:

For some reason I just smile at that! :D

:D :D :D It took me a moment to figure out what you were talking about. Then I saw the ballast in the right seat. I thought the whole idea was to get weigh out of the car. ;)

It does have a Torsen type dif, you know. :rolleyes: :p

As a service to my RX-8-driving friends, I will be providing free lead weights to anyone who wants to wants to improve their traction at the upcoming Atwater Tour and Pro.

In other news, who told Barbara (?) to invite Randy Noll to drive her car? http://community.the-underdogs.org/smiley/misc/crap.gif

true, but if you have it setup and driven such that the rear wheel is off the ground at the same time the throttle is being applied you should go take up crocheting sweaters instead :eek:


;)

Re: setup...depends on how much advice I've taken from my codrivers. :o

hehehe sweet looking picture. i think i soo need some suspension mods and it's time to go play:D weather is finaly nice enough to go out racing again:D

I'd rather be fast than have neat looking pictures. :( Only a little over a month until Toledo :eek:

Jason, I'd like to be the first to encourage you to remove your cats and start shooting flames. I promise I won't protest you. :cool:

Only I am allowed to call her "ballast!"

And only when she's not within earshot. :p

Update, ordered the parts from summit. Now I need to schedule some welder time to knock this out.

Jason, thanks for posting the info. We had a similar exhaust in mind but were worried about sound levels.

JV

Might want to check on the car owner for scheduling too. :eek:

Why would I do that? :confused:

******FYI******

If you are planning on using a trailer hitch, the one hitchweb sells, you will need to make a small change to my exhaust system. :mad: I did not have the hitch, or plans for one, when I built the exhaust. In an effort to move all the weight I could to the right rear I put the muffler so far over it will get in the way of the pass side forward mount.
Options for a fix:

1. Rotate the muffler 90' so the wide part is up/down instead of front/back.

2. Use the J bed for the inlet and the U bend for the outlet, this will move the muffler into the center of the car more.

3. Use the 12" long Borla, the shorter case will clear the hitch, butt it is loud.

4. Relocate the pass forward hitch arm. The hitch was an afterthought for me and it will only be on for local events. So we will change the arm by bending it and mounting it in a different location that does not interfear with the muffler.

Has anyone just tried running no muffler ? Im pretty sure its legal for stock(correct me if Im wrong). Im thinking about it for the Wendover Pro (no sound restrictions).
My only concern is it being just too loud. Has anyone tried it ?

that's what I'd do where there is no sound restriction, but you better have an alternate plan for places like the stadium in San Diego

most minimum weight is to just put a turndown on the mid-pipe exit, all the noise underneath the car will reverberate into the cabin though, probably not a good idea for a daily driver

if you ran a pipe all the way out the back you can put a clamp-on elbow on the end of it to steer the sound away from the sound meter station :rolleyes:

We installed this setup yesterday. Thanks to Jason for reminding us that simple problems usually only need simple solutions! :D

We didn't really do anything different except use an OE midpipe that I bought from Mazmart to cut up. This way, I still have the entire stock exhaust that I can bolt right back up when I eventually sell the car if it doesn't go to an autocrosser (thanks for that suggestion go to TeamRX8). A minor difference was that our hanger wire is welded to the muffler under the exit pipe instead of above it. :eek:

Anyway...A few pics here...

http://teamwtf.org/gallery/albums/al...nstall_093.jpg

http://teamwtf.org/gallery/albums/al...nstall_096.jpg

http://teamwtf.org/gallery/albums/al...nstall_065.jpg

looks good :D

wimp :p ....... https://www.rx8club.com/showpost.php...4&postcount=12


ps: what's that ringing noise?

what are you gonna do? :dunno:

;)

The way that exits is kinda 1980's 911 Turbo-ish. I like it.

My arm is very photogenic. :p

Also, I seem to recall there was video... :confused:

BASTARD... Showing off those Koni Doubles in your pics. :mad: :D

http://forums.carmudgeons.com/images...smiley-014.gif

:p

discuss it with alex :confused:

WTF kind of team is this?? :o

the answer is the question

What, you think you're some kind of Jedi, waving your hand around like that?

http://www.austech.info/images/smilies/new/lsvader.gif

Well, as of yesterday, we have another convert to the Isley "system". Total cost is about $160, buying the Borla from Jegs ($15 cheaper than Summit). Time to fabricate, weld and finish was about 3 hours, mostly because I took my time to make sure that I was happy with all of the measurements. Looking back, I could have basically eyeballed it, thrown it up there, tacked and then laid the final beads and it would have been half the time.

I ran with it today and the car seems to spin up a little faster, but I'm sure that's just psychological (like, my car is always faster right after I wash it, I swear!). It's nice to get rid of the whirring "electric car" sound of the stock RX8, but the 16" Borla is quite a bit louder at freeway speeds (no "old man" comments, Jason, I'm only 43 fer cryin' out loud). My friends did ask when I'm getting the coffe can tip, to go with my ricer sounding ride... :mdrmed:

Summary: easy mod, now that Jason has spec'ed it out for us. Nice sound and an easy way to drop some weight!

I am sure it is no louder than the Z06 was, you just need to adjust to the tone. :mdrmed:

Ran today, mine now has 20k miles on it, and the db person in San Diego told me I hit 89.9 db @ 50'.

Yep, I think that's it, the "tone" is different. I actually think it sounds about as good as any rotary I've heard...

The guys who were giving me crxp all drive V8 powered cars, so you could say they're a little biased!

I reinstalled the OE exhaust on Friday and now that this thread has been brought back from the dead, I have a few new observations.

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I had forgotten how much engine noise and how little exhaust you hear with the stock exhaust compared to the Borla.

I also started it up without the exhaust on at all. After listening to some people around here, I expected something more, uh, impressive. I had my wife rev it up to about 8k a few times. It wasn't much louder than with the Borla can. A little, but not much. Overrun was a little more cool, but overall I was pretty disappointed. Just offered FWIW.

for those that have this custom setup...
are you guys running it catless??
i have a b&b 2.5" midpipe w/ resonator & i'd like to throw on this custom 2.5" exhaust to match it, but i'm a bit worried about the sound...
you can't beat this in terms of weight savings and money, though.
great thread!!!