Okay, let me start by saying that these aftermarket exhausts are way too much money for me! I do realize the amount of engineering and all that goes into the mufflers but come on! I think the cheapest i've seen is in the $600...Borla's MSRP is $800+! Some over $1000!!!

So what i'm wondering is has anyone done their own exhaust work? I'm thinking you could get a single inlet and dual outlet installed and Y off that to the tips. I haven't really got underneath and checked out the space i'm working with but my buddy and I got to talking today and I was just wondering what others have done.

Let me have your input please.

Thanks

 

I've seen people reuse the majority of the stock exhaust and install dual 2.5in-2.5out glass packs...never heard it in person though.

You could always get creative with the rb furai-style exhaust.

If you can weld, I'm sure you'll figure something out. Be sure to post your results when you do.

 

I know a couple of people have taken their cars to shops and had custom exhausts put in. Ive heard anywhere between 300 and 700ish for those.

and mcain is right, you could probably reuse much of the stock exhaust and keep it at a 2.5 inch setup for fairly cheap.

OBX is a cheap exhaust 300ish i think. I know its not as big of a name and it is "cheap", however people on here who have purchased it have seemed overall pleased with their purchase

 

$300 is more reasonable...besides from what i read there isnt much hp's to gain in exhaust upgrades, it's more for sound, right?

After looking underneath the car i see that I would need a Y pipe and then 2 mufflers and some mandrel J bends and some tips.
My buddy and I were pricing some things out and it looks like $140 for two Magnaflow mufflers, maybe $20 in mandrel bends and whatever for some nice tips...
My buddy and I believe that with any car you get, the first thing that needs to go is the stock exhaust!

 

I've debated this, I just don't want my car to become Obnoxiously loud right now(if I added a turbo I wouldn't care but in stock trim, no sir).

When I look under the 8 for the exhaust setup I think back to the days of F-body Camaro's and Firebirds. They had a massive aftermarket of mufflers by dynomax, flowmaster, Magnaflow, etc. The setup is basically a single in with dual out from one muffler.

Look at just the muffler in this image and you will see what I mean. A (good) local shop will most likely sell this type of muffler(just tell them firebird/camaro and they will know what to look for).

If they truly are good it shouldn't be rocket science to match this up to our car with a little fabrication. Some nice quality exhaust tips and you should be in business. Total cost, depending on where you go, will most likely be around $300. Could be less if you find a cool shop.

I am seriously debating about doing this, I bought some big *** muffler tips to slip on over the factory ones for the look of aftermarket. Problem is my tips are so big even with the clamps they don't fit on the OE pipes. I would need to get them welded. I'm in a serious debate to replace my muffler with an F-body muffler from Magnaflow. I'm just worried how it will sound.

 

fyi, here is one example (single tip)... https://www.rx8club.com/rx-8-parts-sale-wanted-44/3-custom-exhaust-magnaflow-single-exit-197983/

 

Has anyone found a place that sales the flange after the Cat? I am going to just make a turn-down pipe but I haven't been able to find that flange. I don't want to cut my current exhaust I am only going to use the turn-down for track days and auto crossing.

 

Mine was put together at a local muffler shop for around $350. Single Borla 1-in 2-out Magnaflow 4" tips. Had it now for 3 years.

 

If your plan is to do it your self.. Its not hard. and If you are.. go with a dual res mid pipe with custom exhaust if you want to see any real power gains. The Agency Power Dual Res goes for about 230$ shipped and the piping you can do your self for under 300.. So.. about 550 give or take if you want a good sound and power gains.. However maybe you can weld better then I can.. LOL

 

That is a very interesting setup! I kinda like it

 

I'm thinking this setup is the way to do it. I mean seriously, this is really all the borla system is but for way more money!

 

if your really looking into this.. check with state emission laws as well as dB sound laws before preforming this. THe sound is a little extreme at times.. If I can suggest anything. Get three glass packs one right after the mid pipe and then the two after the Y spit. I would have done this and tucked away the piping a little nicer, but I'm lazy and this sounds good and works..

 

This is what I was refering to. It looks pretty good, can you post a sound clip so we can get an idea of how it sounds? That would be awesome.

Redline,

I like your setup too, this looks pretty damn unique. Did you make the pipe that goes between cat and the res? It looks pretty high quality in the pics(Titanium)??

$550 is a bit much for me personal that I would spend on custom work, for that price you can get a cat back already. However, I do like how unique the setup is, it would be a tough call.

 

Except redline's 550 includes a mid-pipe which is where the best gains are found in our car. Rumor has it that eliminating the bottleneck can further enhance the flow, although I have not seen any proof one way or the other

 

Megan's Racing also includes a midpipe that replaces the cat. For about $550.

 

Okay I didn't catch that the first time around, where is the mid pipe from or is it custom made also? I've read that there is a good bit of power to be picked up on swapping out the mid pipe alone. If I were going after HP gains I would skip on a catback and just go mid pipe. I think peeps in this thread are looking for sound on a budget though, at least that's why I keep coming in on the topic :-)

 

The guys on my team want me to develop this same exact thing with the resonator we are using for our midpipe but the problem is that sound-attenuating devices have diminishing returns when they are used in series and, as such, would be less effective per dollar spent. A similar alternative would be to use mufflers of different designs in series because they would, theoretically, be focused on different areas of the exhaust frequency spectrum and would lead to a smoother sound.

This is what we are doing with our own midpipe and forthcoming cat-back; both the resonator and muffler are devoid of any kind of internal packing (so they will never burn out or change tone over time after the initial break-in) but they are each designed to deal with different sounds so whether they are used alone or together they sound real nice.

 

That's an interesting (& good point). Thanks, for chiming in, Charles.

I've been following your updated midpipe/upcoming catback thread for a while, and I am greatly looking forward to the release (as, I'm sure, are many others on the forum).

 

I agree with Charles.. the glass packs do where out rather quickly.. however finding a small ,tightly made muffler is hard on its own and trying to put two in is near impossable. Now I have found a few mufflers that would work.. but.. Its a far chance that you could build it all under 500.. The best pipes I have seen are straight ups.. Where its a race pipe spilt with a Y and ran to the end, minimal bending.. This would best suit the car , but the down side is the noise. LOUD!!!!.. I have a vid of mine without the packs. its loud..

If you look at the flowmaster super 44s they are perfect for the sound but the size wouldent fit unless you had it centered and then T piped it using the muffler as a T this would be most likely the cheapest route to take.. But the perfect set up is..

For HP gains + solid sound.
Header ceramic coated and thermal wrapped- 3in dual res mid pipe - 3in pipe - Y split- twin straight pipe mufflers and large tips to show off.. Using light bends.. More of a smooth rolled tubing rather then wrinkled bends.

what would be cool for a nice sound and power.. an electric turbo or supercharger style high rpm fan pulling the air out , placed somewhere behind the mid pipe.. would be like a squire turbo like deal.. Amazing sound .. good gains. and more then likely a cooler running exhaust due to the hot air being pulled.. and the flames would most likely disappear as well.. Fan would break up the burst.. just an idea.. wish someone would play with it..

 

We haven't found any benefits from ceramic coating, whether in an N/A application or F/I application. Thermal wrap helps a bit for interior temps, especially on the passenger side of the car, but not for power. The theory is solid but the vast majority of heat is in the gases and friction (called "entropy") in the exhaust system so even the mathematical gains are nil by comparison. Dual resonators are a waste of money and cause poor fitment. See my previous post. That is why I REFUSED to offer a dual-res midpipe; I was determined to design one that did a similar job with one resonator and would last virtually forever. I found the sound but the durability was a BITCH to verify (but we have done it!). 3-inch pipe does not necessarily flow better than a 2.75 but it does make the exhaust a little louder and deeper sounding. Straight-flow mufflers do not necessarily flow better than cross-flows, while they are louder, and when the packing in them breaks down they actually flow worse and lose h.p.

As for the next idea, without intake/exhaust overlap (as in the Renesis) this idea would not help anything at all.

Sorry to be a parade-pisser but this is what I have to offer for an opinion, and all this will be demonstrated with our midpipe and cat-back.

 

All of my info is basic.. Its not broke down like Charlie's is. I just base the info I know off of cars I've owned in the past. Now given this is a rotary, the back pressure would be a bit higher I'd think, knowing that the sheer heat this motor builds is crazy.. Now.. I did own a 98 GTI VR6 golf. The 2.8 V6 sits at a 15degree rather then a normal 90 or 60 like most. Which givens a smooth power curve but builds heat like a mad man. The thremo wrap and ceramic coating dont do crap for hp.. but the heat is dropped in a large amount. knowing that. I figured something along the lines of that would also work in the ren. I can be wrong, not an expert. But in thought it would work. The 3in piping is a good Idea, I say that cause the sound is better.. The ren is a higher pitched motor then I have owned before and tends to get... umm.. annoying after awhile. So a deeper little more throaty growl is better then a weed wacker. my opinion..

 

BHR agrees with that perspective and that is the tone we were shooting for when developing our midpipe and cat-back. With the cars we have tested the concepts on, we nailed the tone. Plus, we discovered something peculiar (and beneficial) about our midpipe; it deepens and smooths out the exhaust note but it also allows the individual character of each particular cat-back with which it is used to retain it's original sound. OEM cat-backs sound like an OEM cat-back, but smoother and deeper. Tanabe sounds like Tanabe, Borla like Borla, and so on. Many midpipes are so "buzzy" and droning at 4,000 RPMs that they make every cat-back sound the same.

 

^ if you're going to remove the purpose of the muffler why not just remove the pipe from the cat-back...

 

I'm glad you've not started a new thread.
But you've bumped a very old thread

 

I went with the raceroots single exit exhaust.
Got it for 350 new.
It's incredibly light compared to the stock catback.
Its loud, which I like.
And Shoots some pretty massive fireballs (no cat)