ok, im interested in getting exhaust...and i know there are none available pretty much right now....what my questions are, is there going to be exhaust by anyone coming out reasonably soon? and secondly....what does anyone think of custom exhaust...for example buying N1 tips and getting your own piping ran?(3 1/2" maybe)...these are all just random thoughts at 3 13am!

andrew

you can get exhaust now but its like a grand. Try corksport.com or rotartyextreme.com or mazdatrix.com

The big names in exhaust are working on it - don't jump in too soon for the first one you meet....

Mr. Borla himself posted that he would soon have one ready, (and was spanked for 'advertising!')
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doc

Racing Beat has several protype exhausts running around L.A.
One was installed on the Mazdatrix car at the BBQ last weekend
ans also seen at the 2nd Tustin Meet. Also heard that Magnaflow
will have one out soon.

what about the custom way? buying tips and then getting piping ran? or is that not a good idea??


andrew

Not really, because the shop will need to choose/fab an apropriate muffler, choose pipe diameters, etc. Do you want to loan them your car for a few weeks while they trial and error some different designs (and dyno them)? Or would you rather have them guesstimate the variables, slap it on, and hope for a gain? I'll wait a while, until some tested and true units become available.

Originally posted by B-Nez
Do you want to loan them your car for a few weeks while they trial and error some different designs (and dyno them)? Or would you rather have them guesstimate the variables, slap it on, and hope for a gain?

...what about that third option of telling them how you want it?? ;)

So between Auto Exe and Mazdaspeeds exhaust, which one yields the best hp gains? I can't seem to find that info anywhere. Also which one would sound the closest to stock?

Originally posted by ZoominRex
So between Auto Exe and Mazdaspeeds exhaust, which one yields the best hp gains? I can't seem to find that info anywhere. Also which one would sound the closest to stock?

From my understanding the Mazdaspeed exhaust has NO HP GAIN -- only a "more pleasing exhaust note" -- meaning it makes it sound meaner but not go faster.

Originally posted by Doctorr
The big names in exhaust are working on it - don't jump in too soon for the first one you meet....

Mr. Borla himself posted that he would soon have one ready, (and was spanked for 'advertising!')
.
.
.
doc

Try Scott (in the service dept.) at Thousand Oaks Mazda/Subaru . 805-371-5555.

He has extensive info regarding all the available aftermarket upgrades for the RX8. Including all the available exhaust upgrades.

Originally posted by RXhusker


From my understanding the Mazdaspeed exhaust has NO HP GAIN -- only a "more pleasing exhaust note" -- meaning it makes it sound meaner but not go faster.

What does this Mazdaspeed exhaust cost?

the mazdaspeed kit is like 1000 bucks, which is way too much if you ask me, especially if there are no hp or torque gains, anyone that spends that much for the "sound" of the exhaust is just stupid if you ask me

Originally posted by gr8rx
the mazdaspeed kit is like 1000 bucks, which is way too much if you ask me, especially if there are no hp or torque gains, anyone that spends that much for the "sound" of the exhaust is just stupid if you ask me

The stock exhaust is quite restrictive and there are about 8-10hp to be gained from an aftermarket exhaust.

You can easily find a 100% T-304 stainless steel, mandrel bent, straight through exhaust that will provide a 10hp gain over stock for around $550.

Try Scott (in the service dept.) at Thousand Oaks Mazda/Subaru . 805-371-5555. He has extensive info regarding all the available aftermarket upgrades for the RX8. Including all the available exhaust upgrades.

I'll be shocked if anyone buys a $1000 exhaust system that doesn't provide any performance gains. What's up with that?

magnaflow blows, borla is american, its all about Re Amemiya guys! Proven 12.25 bhp gain on the dyno.

That's interesting...I thought I had read that the stock exhaust on the 8 actually was not all that restrictive, as less muffling was needed for the Renesis than for previous iterations of the rotary. It also doesn't really make sense to me that Mazdaspeed would come out with an expensive exhaust that had no performance gains. Mazdaspeed stuff is not usually like that...certainly, if it were relatively easy to get horsepower this way it doesn't seem logical that Mazdaspeed would have missed that.

I wonder, if you are able to come up with an exhaust that gives 10 hp better peak power, what it does to the torque curve? I would think very few people would be interested in 8-10 additional peak horsepower if that meant narrowing the useful part of the torque curve and moving it higher in the revs.

jds

Originally posted by david borla


The stock exhaust is quite restrictive and there are about 8-10hp to be gained from an aftermarket exhaust.

You can easily find a 100% T-304 stainless steel, mandrel bent, straight through exhaust that will provide a 10hp gain over stock for around $550.

Try Scott (in the service dept.) at Thousand Oaks Mazda/Subaru . 805-371-5555. He has extensive info regarding all the available aftermarket upgrades for the RX8. Including all the available exhaust upgrades.

I'll be shocked if anyone buys a $1000 exhaust system that doesn't provide any performance gains. What's up with that?

Originally posted by wakeech


...what about that third option of telling them how you want it?? ;)

true that...

hehe has anyone taken their exhaust off? with the whole thing or just the rear section? i was just wondering....


andrew

I'm surprised nobody has tried a straight thru single pipe design ala Porsche. When I saw my RX-8 up on the lift a week or so back, the exhaust tubing looked like a real good diameter, but the dual exhaust design looked like it did nothing for the performance of it. Lots of sharp bends and needless length for the sake of a dual exhaust. The centered single exhaust seems possible if you change out that real bumper cover. Now THAT would be cool (and probably some serious HP gains to boot).

I'd love to get the HP gains, but I prefer the classy/sleeper exhaust notes. Is it possible to get good HP gains without that "pissed off bumblebee" (can't remember who said that) sounding muffler?

I'm surprised no one has mentioned getting rid of 1 or 2 of the THREE cat's on the car...

Originally posted by rxtreme
I'm surprised nobody has tried a straight thru single pipe design ala Porsche.I'm seriously considering fab'ing up something like that to use at the SCCA Solo II Nationals next month. Noise is far less of an issue than HP in that environment.

Originally posted by Section 8
I'm surprised no one has mentioned getting rid of 1 or 2 of the THREE cat's on the car...

three cats?? where?? diagram please. (i've only seen one...)

Originally posted by wakeech


three cats?? where?? diagram please. (i've only seen one...)

I'm looking now, I've seen sideview pictures that indicate there are 3 cats on the car, but now I can't find them.

Is increased noise a necessary consequence of higher performance exhausts? Are there HP gaining exhaust systems without noticable increased sound?

OK, I know next to nothing about cars, but I've seen several threads talking about how replacing the exhaust could free up around 10 hp. For $500-600, that sounds like a good deal. Especially since Mazda just game me $500 for taking it away :).

Is there any risk in doing this? What are the downsides besides having a louder car? I live in Minnesota so I don't think I have to worry about any emission problems. Is there anyway this could actually hurt the car or make it less reliable?

Changing exhaust sounds a lot safer and more legal than flashing an ECU.

Thanks in advance for any info.

changing the exhaust shouldn't cause any problems. I know I'm gonna change mine. I'm in ca and I do have to worry but mainly just about cops if my exhaust is too loud.

First off, there are a few components to the exhaust. There's the catalytic converter, or cat, that's closest to the engine. Then, there's the "cat-back" section, which is literally from the cat back to the tailpipe.

Legally, you can change out the cat-back section of the exhaust. By law, you can't do anything with the cat, but in many states it's kind of a grey area - it's illegal, but so is taping movies off HBO. No one really checks up on it.

There's also the exhaust manifold - this is a cast iron hunk bolted right to the engine, and the cat is bolted to it.

When designing the exhaust system, Mazda (as most car manufacturers do) had a number of objectives -

- It had to be quiet.
- It had to not rust out before the warranty expires
- It had to be relatively inexpensive
- It has to pass VERY strict federal emissions standards
- It has to be easy to install on the assembly line

ALL THOSE factors are looked at BEFORE performance.

With that said, Mazda has traditionally made VERY restrictive mufflers on the RX-7's. Rotaries are VERY loud, and as I'm sure you know your car is VERY quiet. The only way to accomplish this is with a massive, restrictive muffler.

The cat does quite a bit of sound muffling as well. Even if you had no cat-back on the car at all or just straight pipe, the car wouldn't be THAT loud. It would be loud, though :).

Aftermarket exhausts typically are better built and of higher quality components than stock, and one of their first objectives is making more power. They will be louder than stock, but with just a cat-back, a good exhaust will have a nice, deep, sporty sound, but not loud and obnoxious.

Aftermarket parts to replace the cat are typically called midpipes or straight pipes. Again, grey area, and you can't pass an emissions test with one, but power can be gained there.

The stock exhaust manifold is replaced with headers, which typically is a tubular manifold that keeps the exhaust pulses separate for more power. Many headers are legal - they bolt to the engine, and the cat bolts to the headers.

Right now, there isn't much out there exhaust-wise. In a year, you're gonna see TONS of options - rotary powered vehicles have always attracted enthusiasts, and enthusiasts like modifying cars.

Changing the exhaust should not lead to any reliability problems - just more power and a better sound.

Dale

why doesn't anyone want everyone to hear them coming

Originally posted by rodmeister
Is increased noise a necessary consequence of higher performance exhausts? Are there HP gaining exhaust systems without noticable increased sound?

Yes, there are aftermarket exhausts that do not increase the decible level of your exhaust. However, the tonal quality will be different than stock.

In our case, the Borla exhaust for the RX8 has a deeper, throatier exhaust note than stock without it being louder. There is no resonance inside of the cabin, we worked very hard on this.

Originally posted by rodmeister
Is increased noise a necessary consequence of higher performance exhausts?

in a word, yes. a traditional muffler absorbs the pressure waves of the gasses coming out of the tailpipe, to eliminate the pressure waves which would then come out of the tail pipe and hit our ears as sound. you can't remove energy from the exhaust without hindering its egress from the engine.

there are other muffling techniques, like resonators, or high-tech mic-and-speaker theoretical systems (like an electronic dynamic resonator) which would just modulate the pressure in the tail pipe in complement to the pressure waves in the exhaust to neutralize any fluctuation, but resonating baffle units aren't necessarily more effective at reducing sound or allowing exhaust to flow unimpeded, and the high-tech solution is as rediculous as it sounds.

edit: actually, not quite. if you have two systems (one a straight through, perforated core muffler and the other a contorted dual-outlet glass pack) which have the ability to reduce noise emissions equally, one exhaust path will inherently have less back pressure than the other. if though, you're comparing two identical exhaust paths, with one absorbing more sound than the other, the louder one will be more effective.

also, the tone of the exhaust note can be changed with the size of the tip you put on the end, not to mention the volume of the resonating chamber and other thingies too...

Originally posted by mikeb
why doesn't anyone want everyone to hear them coming

Because it's annoying as hell and I respect my neighbors....

are you serious

Originally posted by mikeb
are you serious
Naw, just joshin ya bro... :confused:

Of course I'm serious. I hate those punks that wind out their cars with that annoying rice sound down residential streets at 2AM (a la one ricer at the end of my street), let alone over-blown bass that people install for everybody else's "enjoyment".

Besides flossin' with your car is for people who have nothing else to offer the world. Don't get me wrong, I'm proud of my car, but, no I don't need half the city hearing me coming a mile away....

I already have the bass (2 12 inch subs) in my 8 and I can't wait to get a mazdaspeed or greddy exhaust. When I do maybe we can meet or I'll see you in San Diego buddy, so you can check it out

What about the twinloop design used by Mugen? I've heard good things about that design (good power gains with a good sound--not too loud). I'm not even quite sure how it works. Maybe Wakeech or Mr. Borla can elaborate.

Also, Mr. Borla, if you could elaborate on your exhaust system for the RX-8 a little more that would be great.

im guna remove my cats(just 1) tomorrow, just to see what it sounds like :-)



andrew

Originally posted by RotorMotor

Naw, just joshin ya bro... :confused:

Of course I'm serious. I hate those punks that wind out their cars with that annoying rice sound down residential streets at 2AM (a la one ricer at the end of my street), let alone over-blown bass that people install for everybody else's "enjoyment".

Besides flossin' with your car is for people who have nothing else to offer the world. Don't get me wrong, I'm proud of my car, but, no I don't need half the city hearing me coming a mile away....

I agree!!!

Originally posted by panda
im guna remove my cats(just 1) tomorrow, just to see what it sounds like :-)



andrew

Tell me if there are 1, 2 or 3 cats then, I think I'm leading the masses astray..I can't find any supporting evidence of my previous statement. Maybe I was drunk or something at the time...

I will be bringing my car into the shop for custom exhaust. Only problem is the small outlet that cannot fit canisters rather just smaller tips. also I will be dynoing the performance gains also. hopefully getting a titanium system. BTW: This is all gunna be legal, so no $1000 fines for me :)

post info and pics- who is doing your work on the 8

Originally posted by Efini 8
I will be bringing my car into the shop for custom exhaust. Only problem is the small outlet that cannot fit canisters rather just smaller tips. also I will be dynoing the performance gains also. hopefully getting a titanium system. BTW: This is all gunna be legal, so no $1000 fines for me :)



Will it be a cat-back? How much will it cost for just the materials (titanium)? What do you anticipate the weight savings of titanium will be over stainless? What will the labor costs be? Who is doing the labor? Will they be welding with titanium? Will the flanges be titanium? Whose mufflers will you be buying? Will they be titanium as well? How long will your vehicle be out of commision?

This is a very exciting project. Please keep us posted.

since im all about attention grabbing (duh, i drive an rx8!) , i want to know what kinda flames people are spitting with their aftermarket exhausts. ive heard the borla can yield some good ones at high rpms, but what about any of the other aftermarket exhausts? any pics, vid clips, etc?

i was hanging out with a friend of mine who happens to own a FD....he was making me have flame throwing envy :o

djmano, just be prepared to be "flamed". Not by me, but all of those "rice-haters" in the world.

just get a plug and tap it into you exhaust. run power to it with a switch in your dash. whenever you want to shoot flames flick the switch. in some cars you would have to enrich the AF ratio but in this car you won't have to.

If the guy had a catless FD it doesn't need any "cheating" with plugs in the exhaust. Now, my FD still has its cat, and I've never seen it shoot flames. I'm surprised the RX-8 is doing that with just a cat-back...

jds

who's cheating? he wants to shoot flames i gave him the quickest and cheapest way to do it. learned it from my dad and uncles who used to do it to hot rods in the 1950's and i'm sure it was done before that.

Originally posted by KC_RX-8
djmano, just be prepared to be "flamed". Not by me, but all of those "rice-haters" in the world.

I agree. Not rice. A nice effect. At the perils of being accused of rice myself. My teenager is really pressing me to put red neon undercarriage lights on, and I'm seriously considering it. I think it would make the car look more sweet/badass at night. Tonight we saw two cars with them, one with blue lighting and one with green, they both looked great.

On a related note, I've had comments that the car is Sweet and "what a badass car". Badass a little more than sweet. Is the 8:

Sweet;

Badass; or

Sweet and Badass.

I think it's both at once!

What the hell, flames???!!!!!

This is my first rotary, do they spit fire?????

there is something about the rotarys engine that naturally lets it spit flames. im not really sure what the mecahnics are behind it, maybe someone else on the board can give us a good explanation.

btw.....although attention grabbing gimmicks are usually known as rice i believe that natural bursts of flame out of the tailpipes is not only one of the coolest things you can see, but one of the most indimidating.

Catalytics do everything possible to prevent flames. They take care of all that unburned fuel. As long as they are working, you won't get decent flames(if any at all).

Get rid of the cat and you'll have flames with almost any exhaust. That means you'll need a SESeliminator(02 tricker).

The RX-7 was able to spit flames because of the overlap in the intake and exhaust ports. The old 13b was also bridge ported for more horsepower by many racers and this made the flames even more visible.

The Renesis Engine does not have this overlapping problem, so I would not expect to see any natural flames.

What I have observed with the Borla exhaust is that you do get flames if the car has been driven hard and has had enough time to get the exhaust very hot.

You can get a burst of flames, along with a pop or two, by quickly lifting off of the throttle after it has been wide open (pig rich).

If the exhaust is hot enough, you will end up with continuous flames out of the tips (predominately the left tip) by just running under full throttle.

I'll see if I can capture it on video this weekend.

before i had traded in the FD i had a full exhaust setup with no cat and shot flames all the time. this occured usually when i got backfire because of the low amount of pressure build up. it makes a popping sound as speed racer stated and will just shoot flames everytime it popped. i haven't knoticed any popping at all in the stock exhaust setup on the rx8.

Dan

Originally posted by deadrx7conv
Catalytics do everything possible to prevent flames. They take care of all that unburned fuel. As long as they are working, you won't get decent flames(if any at all).

Get rid of the cat and you'll have flames with almost any exhaust. That means you'll need a SESeliminator(02 tricker).

this is precisely it. you can shoot flames in ANY car you want, not just a rotary... but yeah, they happen to be much better at it ;)

this is because of the inherently less efficient combustion chamber shape of the wankel engine, and also why they get low fuel economy (no, this has little to do with consumption problems of the RX-8, i'm simply saying you'd never see a wankel in an economy car application).

the overlap between the intake and exhaust of the heavily ported semi-perhipheral 13B's creates tons of breathing at high rpm (seeing how porting will evolve with six side ports on this engine will be terribly interesting), and what really brings the flames is the earlier opening exhaust port, sans catalyst.

simply because the RX-8 doesnt' have any overlap doesn't mean it can't shoot flames like crazy, as speedracer attests to (even with cats). the rich mixture of the intake charge is what's leaving the soot on your tail pipes, so ignite that, and you've got your flames.

hmm.....im really tempted to go catless. however, i live in california so theres probably little chance of that going over too well.

sure the fire shooting out of exhaust is cool... but the consequences for getting caught with that is freakin HORRIBLE. you can ahve your car confiscated in CALIFORNIA and crushed... you could catch someone on fire - like we have ENOUGH DAMN FIRES HERE ALREADY! (ash is raining here). and you can seriously hurt someone by shooting flames at objects... I would only do this on a track car or PURELY show car you do not drive all the time. Think before you do something stupid, please!

Originally posted by Efini 8
you can ahve your car confiscated in CALIFORNIA and crushed... you could catch someone on fire - and you can seriously hurt someone by shooting flames at objects...

um, are you kidding?? :confused: i've never seen any car (less those which have fuel feeds and igniters right at the exhaust) that actually projects a meaningful amount of flame out the exhaust: when a car "shoots" flames, it's a pop of uncombusted gasoline going up (in a rather unclean fashion) once it hits the oxygen rich atmosphere combined with the heat of the exhaust itself, but this isn't a flame thrower, it can be as much as setting a marshmallow on fire for a few seconds (not a fire that's actually gonna burn anything). maybe soot-up the paint around the exhaust tip something nasty, but that's it.

I actually got a few pops out of the stock exhaust when I first got the car. It only happened when I held the throttle full for a second and then let off quickly. I haven't really noticed it since the car has been broken in.

Originally posted by mamccubbin
I actually got a few pops out of the stock exhaust when I first got the car. It only happened when I held the throttle full for a second and then let off quickly. I haven't really noticed it since the car has been broken in.

that's precisely it: the stock muffler and cat keep the car fairly tame, but open it up a little more, and those'll be big back-firing plumes.

Originally posted by wakeech
um, are you kidding?? :confused: i've never seen any car (less those which have fuel feeds and igniters right at the exhaust) that actually projects a meaningful amount of flame out the exhaust: when a car "shoots" flames, it's a pop of uncombusted gasoline going up (in a rather unclean fashion) once it hits the oxygen rich atmosphere combined with the heat of the exhaust itself, but this isn't a flame thrower, it can be as much as setting a marshmallow on fire for a few seconds (not a fire that's actually gonna burn anything). maybe soot-up the paint around the exhaust tip something nasty, but that's it.

Thanks wakeech! You took the words right out of my mouth. ;)

The photo that I posted makes the car look like it's a flame thrower but if they had watched my video they would have seen that the bursts of flame last about a second at most. IMHO it is hard to catch something on fire when it is exposed to heat that briefly.

I agree. Not rice. A nice effect. At the perils of being accused of rice myself. My teenager is really pressing me to put red neon undercarriage lights on, and I'm seriously considering it. I think it would make the car look more sweet/badass at night. Tonight we saw two cars with them, one with blue lighting and one with green, they both looked great.
*Puts Nomex suit on*
I like neon undercarrigage lights too. IMO, the Rx-8 could not be accused of being "rice" if neons were fitted because it has power to go with it. Rice=All show, no go.
Oh yeah, you do get tacky crap for cars I agree with that being rice.
Sorry for going of topic here.

Originally posted by wakeech
um, are you kidding?? :confused: i've never seen any car (less those which have fuel feeds and igniters right at the exhaust) that actually projects a meaningful amount of flame out the exhaust: when a car "shoots" flames, it's a pop of uncombusted gasoline going up (in a rather unclean fashion) once it hits the oxygen rich atmosphere combined with the heat of the exhaust itself, but this isn't a flame thrower, it can be as much as setting a marshmallow on fire for a few seconds (not a fire that's actually gonna burn anything). maybe soot-up the paint around the exhaust tip something nasty, but that's it.


http://216.110.167.205/~dbrace/pics/logos/front.jpg
OK I have personalyl seen several cars launch flames because they are running a highly aggressively tuned fuel mixture. I have seen skylines, silvias, rx-7s, and truenos do this on the track also. rally cars also. in japan they have flame launching contests that extend up to 6-15 feet beyond the vehicle...

here is a pic of a VW Gold GTi tuned by Dahlback Racing... it seems to be SHOOTING FLAMES!

now that is sweet
great pic

My race shops FD with full dp and exh sure belches out some good flames when we are @ the track. I tried to get pics but couldnt catch any. I knew people who would purposely throw HUGE fireballs from rotaries but they were carbed so I dont think EFI will let you do it the same.

bring car to speed, 3rd or 4th gear throttle to floor, kill ignition while throttle still on the floor, wait 5-10 seconds and return key to on position as if you were bump starting it. and BOOOOM a huge fireball will erupt out the back.

Originally posted by wakeech
um, are you kidding?? :confused: i've never seen any car (less those which have fuel feeds and igniters right at the exhaust) that actually projects a meaningful amount of flame out the exhaust: when a car "shoots" flames, it's a pop of uncombusted gasoline going up (in a rather unclean fashion) once it hits the oxygen rich atmosphere combined with the heat of the exhaust itself, but this isn't a flame thrower, it can be as much as setting a marshmallow on fire for a few seconds (not a fire that's actually gonna burn anything). maybe soot-up the paint around the exhaust tip something nasty, but that's it.

Actually, Efini 8 has a point even if it is lost in his hyperbole. Even a hot muffler has the potential to start a nasty fire in dry enough conditions. A good number of wildfires in the last few years have been traced back to 2 or 3 matches or a stray cigarette butt, which would seem almost as innocuous as a flaming marshmallow.

My owner's manual for the SA states that I shouldn't park on a grassy area after a long drive, because my exhaust could start a fire. ;) That's before I deleted the thermal reactor and heat exhanger! I would imagine my RB header/presilencer gets even hotter.

As far as flames go, my car used to spit flames with the stock exhaust, but now that I've deleted my air pump and installed the header system, it doesn't shoot flames, afterburn or make any untoward noises. Kinda boring really. My stock system was good for a backfire that sounded like a rifle shot if I went from WOT to instant decel, like preparing for a turn in autoX.

I need someone tell mi whats heel is this for?
Somebady nouse it?

Good question, I've wondered that too. Looks like an exhaust cut-out of some sort, but if that were the case, I would expect there to be a flange to cap it off for the street, or possible some sort of a bypass valve.

Anyone?

I dont know what that is but i think putting a switch to open it and byspass the mufflers might give you good power on a drag race although loud as hell

If that were a picture of a system for a 2 stroke, say a new Yamaha snowmobile, it likely would be a Resonance Chamber used to cancel a particular frequency.

Now there's a thought!

is that the stock exhaust? or aftermarket? if so what kind?

Aftermarket, and I'm pretty sure that exhaust came from Knight Sports. Check out http://www.knightsports.co.jp/whatsnew-index.html

Everyone is talking about the different cat-backs on the market and how much power they will make. Now, I am pretty familiar with the rotory engine, however, after the exhaust is released from the exhaust port, it must go into some type of manifold before the first catalytic converter. Everyone is concerned with how much power each cat back is going to make. What i want to know is who has the balls to fabricate a race exhaust to eliminate all the cats and have it be stright piping (Or a "high-flow cat") from the motor onward, in order to make the MAXIMUM amount of power.

BTW: I know I am totally ignoring warranties in this thread, but i don't really care. I's prefer if anyone is going to cry about warranties, just dont post in this thread at all.

YES!! I want a full exhaust too! :D

Racing ceramic coated header, ultra high flow, high temp, high performance cat (or no cat) and complete cat back!!

Canzoomer/Harddata/Maurice is talking about doing just this as his next project. Check out this voluminous thread fro more info, towards the last 5 pages or so. http://www.rx8club.com/showthread.php?s=&threadid=11614

We have just dropped off our Project 8 at B&B Performance Exhaust and they will be producing a prototype cat back and cat delete pipe. Should be done by next week. I'm excited! I'll let everyone know when I find out as we are planning to sell the exhaust and test pipe. If you want to learn more about B&B go here: www.bbtriflo.com

Thats awesome! vivid rules. Can't wait to see some numbers with a full exhaust done, with no restricting cats.

its the seam

Nice work Vivid.

everyone is talking about power gains, why aren't we thinking about the weight of the exhaust also? IF you have a good exhaust with good gains, the gains will be noticed even more if the weight is reduced of the system, thats why I say full titanium for weight savings and maximum power gains

From the folks that import Knight products:

--------------------------------------------------------------------------
Hi how are you, that exhaust from Knight Sports runs for over $1100. Our sale price for it including shipping from Japan is about $1430, but we will be working on a large buy at the end of the year from japan so we might be able to save more on shipping

Thank you
Tony
www.rxcret7.com
-------------------------------------------------------------------------

From my question to them:

-----------------------------------------------------------------------------
Hello…
The Knight Sport web page shows what looks like a RX8 CAT back exhaust. If so, what is the price and LT on the unit?
-----------------------------------------------------------------------------

uh huh...hell no.

maybe get rid of the dual tip design too.

My friends and I were bored tonight so we went out and tried to get some flames out of the stock exhaust. They didn't compete with the now-famous Speed Racer flames, but it was still pretty cool. Maybe they could've have been bigger if it wasn't cold and foggy out.

Here's the pic...

those are some hot flames mp. they look like a brazing torch flame. BTW i once say a guy with a pt boat turbin in an old ford t-bucket shoot flames. he hooked up the after burner to the exhaust (like twin 8 ''exhaust) and when activated it shot like 20 -25' flames.

My dad tells me stories about his flame throwing RX-4. It spit some flames under normal driving conditions, but he could make it shoot a good five-foot flame when he wanted. All he had to do was turn the car off while moving and give it some gas and proceed to turn the car back on (huge fireball accompanied with a deafening roar). He went through several exhaust systems on that car.:)

Sweet pic!!!

Originally posted by Sin
Sweet pic!!!

thank you.

The easy flame shooting from rotories are due to super rich conditions. Rotories are known for easy detonation, so they come running pig rich from the factory.

Without a cat, a freeflowing straight through exhaust will cause extra fuel to ignite in the exhaust, hence throwing flames.

As somebody said any car can do it, but I usually see it happening on modded turbo cars running no cat. I didn't have a cat on my eclipse gst with a full 3" exhaust, and on some occasions it would shoot a little fireball with my stock 450cc injectors.

One major misconception.... it doesn't hurt the engine, and i'm majorly anti-rice and I actually think it's pretty cool. But for the cali people it's not a good idea, it's a $1000 fine.

Just wanted to warn: If you have a Borla, and continue to shoot flames for a minute or so, the exhaust will get so hot that it does come out like a flame thrower!!! A continious flame that shoots out even farther whenever the gas is pressed. Saw it happen to a friends car who was trying to impress. He now has dark spots on the heat shield around his cat where he burned it. No engine codes yet, but they will probably be forthcoming. Be careful!

hello everyone, um this is my first post so not quite sure how to do this, but could anyone recommend a way to reinforce the plastic outer housing on the exhaust, because i am afraid that with new aftermarket exhausts they will melt it.

I guess one way would be to buy the exhaust finishers, that may help some.

I've put 250 miles on my greddy so far and it has not been a problem. This is also the largest tip out there. It might eb an issue with canzoomers stage 1, but I'll worry abo9ut that next month :D

The Greddy is a dual also?

Single cat back pipe, dual mufflers, dual exhaust outlet pipes. Some info is here, on Greddy's website (http://www.rx7.com/RPGReddyRX8exhaust/images.html), and more info is here (http://www.rx8club.com/showthread.php?s=&threadid=16442) in the summary post about all exhausts, including dyno charts and audio sound clips. Finally, here's the thread (http://www.rx8club.com/showthread.php?s=&threadid=16863) specifically about the Greddy exhaust, including notes from forum members who have them.

If the exhaust system gets too loud, could one stick a resonator/silencer before the muffler to reduce the sound?

Yup, you could. In fact, some midpipes (replaces the cat) are coming with resonators to reduce the additional sound.

So I don't know too much about how this all works...but I was intending on getting the Borla catback exhaust. But then somewhere along the line, I decided I wanted a more free flowing exhaust set up...but I don't know jack about this subject...

I was wondering..can I remove the cats with the Borla installed? Because the whole term, "catback" makes me think it's necessary for the cats to remain...Also, what's this about a mid pipe I've read about? What is its function and is it necessary if you want to remove the cats?

Basically what I'm trying to get at is, what are some options for me to consider if I wanted a free flowing exhaust set up on the car (that may not be street legal)?

What I plan to get so far: RE CAI, Borla catback exhaust...

Thanks...

(Re-posted as new thread b/c it got hidden in the sticky thread)

So I don't know too much about how this all works...but I was intending on getting the Borla catback exhaust. But then somewhere along the line, I decided I wanted a more free flowing exhaust set up...but I don't know jack about this subject...

I was wondering..can I remove the cats with the Borla installed? Because the whole term, "catback" makes me think it's necessary for the cats to remain...Also, what's this about a mid pipe I've read about? What is its function and is it necessary if you want to remove the cats?

Basically what I'm trying to get at is, what are some options for me to consider if I wanted a free flowing exhaust set up on the car (that may not be street legal)?

What I plan to get so far: RE CAI, Borla catback exhaust...

Thanks...

Thanks Omicron

Nothing gets "hidden" in stickies, they are just where general guestions like this one should go. Otherwise we wind up with 100 like threads when we really only need one.

With regards to your questions, yes, the Borla is a better flowing exhaust than stock. Not a huge improvement, but some. And yes, you can run it without the cat - but you must somehow replace that cat or you'll be missing ~3 feet of your exhaust system! A "midpipe" replaces the cat, and fills this gap, but is not legal for the street.

Exhaust comes out of the Renesis engine exhaust ports and dumps into the exhaust manifold which bolts to the engine block. This manifold can be replaced with a "header" which is a better flowing version of it. Next the exhaust gasses go into the catalytic converter. This too can be replaced with a higher flowing model. The final component is the muffler, and again, it can be replaced with a higher flowing unit. A cat-back muffler just bolts to where the cat ends, or if the cat has been replaced with a midpipe, it bolts to that instead.

HOWEVER, none of these mods will make a huge difference, even when combined, because Mazda did a pretty durn good job of making the factory system low restriction. A header will help most AFTER someone figures out how to regrind the port angles to make the exhaust flow smoothly into it. Next best improvement will be the cat - but at the cost of significantly increased sound. Finally the muffler. Overall you might gain 20-30 HP if you did all mods.

Hope this helps.

I dont know if the guy driving the car on Rotary performances sound/video clip was trying to get a best time, but I timed his speedo with my timer. 0-60 mph= 8.2 sec, 90+ mph= 12.8 sec. anyway it sure didn't take long to get the car past 90 mph and the catless exhaust system wasn't too loud, I'd still like to get a free flow cat or a large resonator to quiet it down some..... Does anyone think Canzoomers stage 2 will burn out a resonator ? Sorry I don't know much about the internal material of a resonator.

Originally posted by strong bad
So I don't know too much about how this all works...but I was intending on getting the Borla catback exhaust. But then somewhere along the line, I decided I wanted a more free flowing exhaust set up...but I don't know jack about this subject...

I was wondering..can I remove the cats with the Borla installed? Because the whole term, "catback" makes me think it's necessary for the cats to remain...Also, what's this about a mid pipe I've read about? What is its function and is it necessary if you want to remove the cats?

Basically what I'm trying to get at is, what are some options for me to consider if I wanted a free flowing exhaust set up on the car (that may not be street legal)?

What I plan to get so far: RE CAI, Borla catback exhaust...

Thanks... My response to this is in the other thread (http://www.rx8club.com/showthread.php?s=&threadid=18207) you started.

Does anyone know if the stock Exhaust has flanges you can unbolt from the cat, as well as the cat having flanges you can unbolt from the exhaust manifold. I need to know so I can bolt the stock system back, in case of warranty issues, Thanks.

Originally posted by Omicron
...Overall you might gain 20-30 HP if you did all mods. Is this for real? Will the HP gain be spread out across the entire power band on a % increase basis? Where's the parts/vendor/price list?

You've gotta keep reading to find the results I'm talking about. My ~30HP number comes from the fact that one vendor claims the mid pipe and exhaust net a 19HP gain, and some intake vendors claim up to 10HP increase from their intakes. These gains are usually available in the mid to upper rev range.

But whether or not these gains are real is the subject of some debate. Racing Beat, who is a very reputable vendor and has been tuning rotaries for a very long time, claims here (http://www.rx8club.com/showthread.php?s=&postid=206825#post206825) that no where near 30HP can be gained from intake and exhaust mods alone. While I see their point, I'm not sure that the other vendors would be deliberately falsifying claims either. So the jury's still out on what can really be gained without major engine work. Fact is, Mazda did a pretty durn good job of tuning this car.

Parts currently available for the '8 are all listed in this (http://www.rx8club.com/forumdisplay.php?s=&forumid=65) forum, and link to dyno charts in many cases.

Hope this helps.

Originally posted by Genom
I've put 250 miles on my greddy so far and it has not been a problem. This is also the largest tip out there. It might eb an issue with canzoomers stage 1, but I'll worry abo9ut that next month :D


What issues do you foresee with Greddy and Canzoomer stage 1 together?

Canzoomer has recomended both the Greddy and Borla exhausts with Stage 1.