???Single or Dual Exhaust???
 

Should I go single or dual on my 13B BIG SP.


2 1/2 Single

OR

2 Dual


Advantages and disadvantages PLEASE.

I already have a dual setup but I sprung a leak at one of the welds.

INPUT PLEASE.


-Ryan

I, too would like to see a chart for recommended exhaust setups from stock 12A NA and EFI, through all the ports, with/without Supercharger, and then the same for 13B's.

Jeez, that would be sweet. Does any one person even know or have all that info ?

Having a dual exhaust will add weight to the car. If there were 2 parts for headers that have thier own cats then I would definately go dual exhaust. Otherwise you might have a problem with the exhaust's air flow.

[QUOTE='//[T.0.P]//']. If there were 2 parts for headers that have thier own cats QUOTE]

Who said anyything bout cats?

You can find all your answers here. Scroll down.

https://www.rx7club.com/2nd-generation-specific-1986-1992-17/need-straight-answer-true-dual-setup-364808/

i was actually thinkin the same thing 2 pipe's all the way back, but i wanted 2 use a dual inlet/outlet flowmaster muffler on it (40 series mayb) but i hear lot's of ppl talkin bout how they cant take the intense heat of the awsomness of the rotary :D so i scrapped that idea, from what i read though 2.25 should prove to be a pretty good performance install, but now what muffler to use though, i didnt want it commin outta both end's like 2nd gen's though, sorry to hyjack this post but what muffler that has a dual inlet would be a good decent sounding muffler for a set up like this on my gsl-se?

lol. Cats. What are those again?

must be a misunderstanding of an unusual abreviation. But then again I could have met you before and pissed you off in some way, happens a lot.

Nah, I don't get pissed off by some people.

I was making a joke reference to the fact that most of us have exhaust systems that no longer have catalytic converters. :D

What???????

Are you for real?

What do you use then? Just a straight pipe? That's crazy man .. how loud is your car?

:D Check out www.racingbeat.com. They sell a real nice exhaust system (including headers) for about $650.

It actually gives the car a more, um, earthy tone.

Ahhh ... this looks very nice. I was planning on getting a high flow cat pipe from the rx7.com website but this looks like the sheezy.

So there's no cat on this thing? Or this that the presilencer??? That looks like a direct bolt on. I dunno what they mean about the factory connecting pipe ahead of the main muffler that doesn't come with the kit.

The presilencer is LIKE a cat, but not as emissions friendly if I'm right. I'm not to quick on exhaust systems stuff. It is indeed a direct bolt on, and not too hard to do (I had help because I didn't have the time to do it myself)

The pipe they're talking about is just that, a pipe. The picture has that pipe as a greyed out peice, and you should be able to identify it by looking at your current exhaust system.

I'm not sure, but I've heard that www.mazdatrix.com has it for a cheaper price (same system).

I'm sure you know by now that the best way to start the upgrade chain is with your exhaust system, and this is probably one of the best ones out there.

I don't know how well it keeps emissions down, though, so if you live in a state or country that requires emissions testing, you may want to ask around about that.

I'm not too worried about emissions .. just how loud it is. I had a 2000 galant before and my friend and I unbolted the cat and man was it the loudest mofo there was.

There's inspection places around here that test just the basic stuff .. lights, windsheild wipers, stuff like that. So the emissions thing wouldn't be an issue.

I'll probably get that once my car is on the streets again. Right now it's just sitting on my driveway. Gotta replace some stuff to get it started again.

EDIT: I couldn't find the page on mazdatrix.com that has the RB exhaust system, but I did see it on mariahmotorsports.com for $613

Maybe Mariah was the place I was thinking of.

http://www.racingbeat.com/FRmazda1.htm

The presilencer is for noise reduction, not emissions.

For a cheap power gain, replace the 3 cats with a pipe fabbed at a muffler shop, RB used to sell this pipe $80., maybe someone else does.

Steve.

Why can't I get the links to go right to the page its from?
Select "exhaust system 79-85 Rx7" from categories at left.

Single 2.5 will give you more low-end. Dual is for top-end

You've never personally had experience with both systems have you? I have. That's backwards.

I had headers to presilencer to power pulse muffler, but decided was too quiet and restrictive and got rid of the presilencer, replacing it with a custom made bolt-on straight pipe. With the power pulse muffler, headers to straight pipe is still not too loud, unless I WOT it. :bigthumb:

If you own a rotary powered car and want power, you really can't worry about how loud it is. No matter how hard you try, an aftermarket exhaust is always going to be too loud (except racing beat, but their exhaust is still too restrictive for some engines). I've been trying to make a quiet custom exhaust, and it still isn't as quiet as I would like. I have 2 mufflers and a presilencer too! My system consists of a saber cherry bomb style muffler (stainless pack I think), largest magnaflow I can fit under the car, and an N1 style muffler at the back with the silencer insert in it and its still loud, but quite free flowing if I take the silencer tip out of the N1.

I have (FB single and RX-3 dual) but I noticed more low end when I switched to single in my FB.. yup, first time to run a single in any of my RX. :bigthumb:

you should have listened years ago...YOu could have killed 84SE out of the bat. :)

That's been my experience so far. I have headers to a 12"glass pack to a MagnaFlow Racing muffler. I wanted it quieter so I swapped out the 12" for a 24" MagnaPack. Sounded perfect for about the first month. Nice wooshing sound and quiet. But I quess our rotaries just burn too hot and three months later it is back to approx what it was before. I've heard that fiberglass begins to break down at approx 1200 degrees F.

Or I quess I can say you can make it quiter if your willing to shell out $100 every two to three months.

Most people aren't willing to spend that kind of money every 2-3 months, just to keep their car quiet. I know I'm going to run into problems in about 4-5 months. I'll probably have more money and time to spend on perfecting my exhaust by that time anyway.

I did kill his SE, even before headers and direct fire, but Pinky is a different story...

So what, are you telling me I should go 2 1/2 from the headers to the muffler?

Had header single pre saliencers (& Primaflow muffler) on my stock 12A & SP 12A. Had singles system on my other stock 12A. Put duel on the SP 13B I have in my current 81 & there is a big difference in power & throaty raspyness of exhaust note. Go w/ the duel & you can always further upgrade your engine later.
http://members.cardomain.com/snapshot1

sorry to hi jack this thread, but i would like to share my results with the exhaust on my 85 gsl-se.

the old suff was rotting off, so i cut it off after the pre-cat (or what ever the first muffler thing is after the manifold). i did away with all of the cats and what not, then i bent some 2in pipe. i thought i could get away with just a n1 fart-can at the end, but it was waaayyy to loud. so i went and got a dynomax to put in midway and a 40 flowmaster to finish it off at the bumper. it has a verry nice deep tone, and i would recomend it everybody. :)

do rotaries like exhaust scavenging like boingers do? if so, i suspect a nice single pipe would be better.

thats where the long primary system comes into play. lots of people say run dual al the way up till just before the muffler then connect them for scavenging purposes...supposed to be the best.

Running a straight pipe from the headers to the gray thingy on the RB exhaust before the muffler might be too loud for me. Not that I would care, just concerned about the noice level, but then again I shouldn't care.

Only thing I'm concerned about is getting pulled over because of the loudness .. otherwise I would use a straight pipe only if it helped my car's performance.

I wouldn't run dual though. That's just more weight on the car, and with the stock motors, even ported I still wouldn't do it. BTW I would like an RX-7 muffler without the dual tip. Find it unecessary as well.

Thanks for all the opinions guys. I decided to stick witht he duals and just get the leaks fixed. I didnt have enough $ for a single 2.5 all the way back.

Well I post a pic of it when its light again.

As far as performance, I can say it runs alot smother. I think this whole time I had a leak, and it just opened up recently cuz it sounds alot quieter than usual npw that its fixed.

Speed wise, I cant really tell.

Oh heres a old pic. I found.

http://img.photobucket.com/albums/v2.../stuff_008.jpg
http://img.photobucket.com/albums/v2.../stuff_010.jpg

heres a pic of my other cars setup.


This one cost a pretty penny....Just look at it...

http://img.photobucket.com/albums/v2...2/f7bd344d.jpg
http://img.photobucket.com/albums/v2...ITE_SE_051.jpg
http://img.photobucket.com/albums/v2...ITE_SE_067.jpg
http://img.photobucket.com/albums/v2...ITE_SE_052.jpg
http://img.photobucket.com/albums/v2...ITE_SE_073.jpg
http://img.photobucket.com/albums/v2...ITE_SE_069.jpg
http://img.photobucket.com/albums/v2...ITE_SE_068.jpg

DUAL INLET MUFFLER ! !

http://img.photobucket.com/albums/v2...ITE_SE_070.jpg
http://img.photobucket.com/albums/v2...ITE_SE_040.jpg
http://img.photobucket.com/albums/v2...ITE_SE_041.jpg

If you are afraid of loudness, then stay away from 2,5" single exhaust. I currently have RB headers, then 2,5" stainless with two Ferrita (extremly good quality) free flow mufflers. The sound is awesome, but loud!

Oh, talked to a guy that lives of welding custom exhausts, and he told me that a 90 degree bend muffles the same amount of sound as 21 feet of straight pipe! I didnt belive him at first, but he then showed me a RX2 with the same mufflers and about the same amount of pipe that i have. The only difference were a 90 degree bend. The car was so much quieter than mine, so i guess it works!

racing beat is a great setup, i have it minus the muffler (the idiot that used to own this car cut it off for a stupid ass ricer fart can). I've heard the setup on iotus' car, he used to have the N1 style muffler and the racing beat sounds beautiful on the car. Not real loud, but deep and just enough to let people know you mean business yet keep your ears from ringing after driving on the highway. So if you're worried about how loud it is without a cat, dont worry, its pretty mild.

As for the true dual setup, i was really wanting to do this, but after reading rotarygods post (which is great by the way, awesome info) im changing my mind, although i would like to hear how it sounds, i imagine its a pretty unique sound from the rotary.

I don't really consider this system to be a true dual system. There is only 1 outlet on the muffler. It jsut collects internally in the muffler. This makes it a long primary. You wouldn't benefit in the power department from making a shorter primary system.

Wish I live further away from work, say a place that requires some freeway driving. Too many weekend projects and being only 5 minutes away from work are not allowing me to do top end and actually compare the two systems. A good topic and very interesting. :crzyeye:

Come visit on a weekend and have some beer! that way you can fly up the 5. ;)

fly like an eagle?

Ryan,

I have a 2.5" piping that I had in my Prelude. Come take if you want.

Hi Ryan,

The green REPU has rb header, dual 1.75" pipe for a foot, then 40" long 1.75 ID glasspacks side by side, then collects into 2.5" id magnaflow, 90* bend and pacesetter dual resonator tip. Pretty quiet. Dellorto makes a lot more noise than exhaust.

I put a lot of sound deadening foam insulation under the hood and around engine compartment. Dellorto is still louder than exhaust! Since u have a dell u can use that as a reference.

Come over anytime and test listen. U got my #

I say...REMOVE THE PRESILENCERS. its too restrictive...w/o it, you have a chance against CRAD51 :D

his presilencers are just like the glasspacks though... straight through, so it shouldn't hurt much

ok...i want to put the rb sp header on my 12a, and just replace the cats with a straight pipe. i've got a magnaflow muffler with new pipe welded up to 18" away from the cat-pipe(the new pipe starts 18" away from the cats, muffler is still at the bumper). would it be too loud straight piped or should i place a muffler inline where the cats are? and if i should use a muffler, which one?

chould be like me and have dule side pipe exhuast 2.25 to cherry bomb to duale side pipe's 3 inc

it really kinda odd sound fine but ti get alot fo looks and plus it done well i mad eit my self caus eno one i know has vere done it

yes it can unless its old and burnt out. But that take lots of years. So it can hurt performance

thanks for all the responce guys.