Benjamin4456

Let's start off with this: for the entire time my car has been on the road I've been running the hacked together exhaust from my parts car that the PO "made"; yeah, it's terrible. Beehive at 3k, 4.7k, and 5.5+ part throttle. It rattles and pings and is just all around awful.

So, I'm finally in a place to replace it and I am looking to go the custom route. I know the RB system gets a lot of praise, but I think it'd be a bit too quiet for me, is pricey, and I'm just up for a project. That said, I've been compiling research for a while, but all I've found are tons of threads from 2007 or something and they never really seem to convince me one way or the other. Before we go any further, here's the run down on the car:

- 74 spec ported 12A
- hogged Nikki carb (24mm/30mm)
- RB collected header
- DLIDFIS
- Carter Fuel Pump and Summit brand fpr

That's probably all the relevant mods. Now, I will say I like an "authoritative" exhaust (as someone once put it). To me that means rumbly and 'louder' but no rasp or buzz. I would still like to remain sane though, so nothing too crazy. Based on what I found I've setup the following main component list:

- 1/8" wall piping, 2.5" dia.
- Magnaflow 642-14258 in the rear
- RB 2.5" universal presilencer in the middle
- Keeping the RB collected header

So I'm curious to hear what y'all run these days. I've heard a lot about Borla and Magnaflow but it seems like both have a pretty good standing. Any advice here is appreciated. Being that it's been nearly 12 years for a lot of the old exhaust threads, maybe some people's opinions have changed. Please do comment, I'd like to get a wide sample set if possible. Thanks.

t_g_farrell

iTrader: (1)

So the thing about your "planned" exhaust is that it will rob you of power because its not dual piped as far back as possible. The reason we all use and recommend the RB SP exhaust is because its made very well, sounds great and most importantly significantly improves performance. The RB collected header is a compromise to allow it to be used with existing mazda exhaust components and the RB presilencers. Yes the RB SP cost a lot. I got mine used (because they last forever) for $400.00 many years ago.

ray green

iTrader: (14)

Racing Beat Ben, Racing Beat.

Even a brand new one at $1,000 will save you trouble and give you a better result.

And when it comes in the mail unpacking that stuff is a trip, it's a piece of art.

And the exhaust note is perfect.

Benjamin4456

EDIT: so my response became slightly long winded, just wanted to clarify that it's not a rant or the like.

Ok, thanks t_g_farrell. I might say one bit though, and that's that given the exhaust parts I listed above, I theoretically would not be losing any more power than I have now. While perhaps I could get more power with a long primary system, that's not the main goal of this endeavor - I should have mentioned that earlier. My main reason for rebuilding the exhaust is to get rid of what currently sounds like a tin can full of rocks mated with a beehive rolling down the highway. I suppose I never actually shared what my current set up is so here it is: RB collected header to a 2.5" 'front'-mid pipe with a blownout Magnaflow 14" resonator (previously used by two other owners and was put in by me because it was better sounding than the cat that had just recently exploded - a "temporary fix"), back half of the mid pipe goes from one 2.5" to dual 2.x (whatever was the stock diameter for 81-82) to a flange, then the stock over axle piece out of an 82, welded to some muffler that has no id. So yeah, a bit of a hodge podge.

While I won't argue against the tone, or quality, or durability of an RB system, from what I understand it's not much louder than stock, although slightly bassier iirc. Everyone has their own preferences for an exhaust in terms of loudness, tone, etc. although I am a fan of the louder side, but to each their own. I just checked RB's site and it states that their full Street Port Exhaust System typically amounts to ~5% power gained over the short primary system. Based on some other threads though, it would seem that because of the compromise RB makes between between civil noise levels and performance, the muffler units are still rather restrictive (relatively speaking, obviously it's a far improvement over stock) than other, 'louder' options. Now I'm just going off what I read, so who knows, but if I went with a less restrictive option, perhaps that lost option of improvement could be gained back slightly while still staying short primary. I'm not one that has much experience in this regard though, so if there's something I'm missing please do tell.

With all that said, here's a few criterion/goals that I'm looking for:
- dual exit exhaust, just visual I know, but I've always thought single exits from a dual exit bumper look strange
- not earsplitting loud, but definitely present
- short primary (unless I can be convinced to do a custom long primary setup)
- be rid of ping, rasp, and hopefully drone although I'll deal with some of it over the other two

I'm eager to hear some more opinions. Be it RB or custom, do share. This exhaust is for a fun car, not a track car. While it's nice to not lose power, I'm not looking to squeeze every last one out of it if it means a more enjoyable (based on my idea of such) experience. If anyone thinks my first listed setup is going to make me wish for earplugs, please say so. If that's the case maybe I ought to change my plans. For context, my current exhaust makes talking when accelerating usually not worth dealing with - not looking to go much any louder than that. Thanks in advance.

Benjamin4456

Ah Ray, you just barely beat me . I guess I should have expected a lot of RB proponents. I get that it's a well built and designed system, but if the old threads tell the truth, I hear it's not much louder than stock. If that's not that case, well then perhaps I should reconsider some things, but if it is, I just don't know about that. Right now it's honestly just fun to a little obnoxious, and sure, while I will likely change that opinion at some point, for now that's how it is. I've heard a few sound clips of the RB system (there are surprisingly few quality ones) and it sounds good no questions asked, although I really don't have a volume reference. Comparing it to stock - which I had at one point - is about all I've got. That said, if it is only slightly more audible than stock, to me that's not worth a grand or more (for now at least). Like I said before, everyone's got their own ideals, mine just happens to be a little noisier I suppose.

I honestly like the current volume level of my car, I just wish it didn't sound like it was falling into a million pieces. The idle rumble, roaring up top; I'm just a fan of that. One day I'll get tired of it, but right now I enjoy it so why not make the most of it. Anyhow, that's my point of view for the time being.

aeenox

Hey,

I am currently running a custom made 2.5 in exhaust. It is made out of stainless steel tig welded. I ended up going with a rotaryworks/ CX racing header, maganaflow presilencer 100% stainless steel. I have tried already three different mufflers. The 1st one I used was a speedfactory lt-5 muffler. It looked great on the car, I ended up getting rid of it because it was too loud. Then the 2nd muffler I used was a DC sports muffler dcm4500. This one also looked really good but ended up blowing out. Now I finally caved and I am running a Racing Beat 2.5 universal muffler, I ended up cutting the tip off the DC sport muffler and having it welded onto the RB muffler. All the mufflers I have tried are made 100% stainless steel. I was just trying something different because I didn't want my car to be like everyone else. Racing Beat exhaust I bet works great but yeah. I would suggest the racing beat universal with a nice tip that you like.
Speedfactory

DC sport

Racing Beat

ray green

iTrader: (14)

Well all I can say is when I exit the parking lot in my RB exhausted 12A everybody notices.

And smiles.

tommyeflight89

iTrader: (4)

I have the RB Street Port system on my FB (12A Streetport weith Dell 48).

What I may try this season is to have a shop fabricate me a new muffler for it that bolts to the original flange. I am looking for a bit louder and would like a tig welded pie cut tip for it. Like Aeenox's first pic above but with an oval muffler.

I think I found a few sound clips of a similar setup and it sounded great. The RB presilencers should help keep it from being too loud.

Was thinking of the RB 3in universal:
Universal Muffler, 3-inch ID for RX7 1975-1985 - Racing Beat
And the mating flange:
Muffler Flange for 81-82 RX-7 - Racing Beat

Benjamin4456

Awesome, thanks everyone for the additional replies. Now you've all got me doing some rethinking. I'm still not for the full RB Street Port system (there's another reason for this I'll mention shortly), but I don't have anything against using their universal parts. In my original 'list' I had planned on their universal presliencer, although I had forgotten they have generic mufflers as well. Intriguing. I also really do like that pie cut down turn exhaust you had aneeox. If I were to go single tip, that would probably be the route I take.

So now then, like previously mentioned, I remembered another reason for me to avoid the long primary setups: I need to be able to stuff a cat in there at some point. That's something I'm actually rather worried about, passing smog that is. I have a feeling that trying to fit a cat on a dual pipe would not be a fun endeavour, not to mention having to cut up the dual pipe or make a temporary replacement one. So that's another reason to avoid the RB SP setup for now.

I'd be curious to hear some additional thoughts on the RB universal mufflers. Are they a baffled or straight-thru design? How's the tone and volume in comparison to those other mufflers you tried aneeox? About an hour ago I was out driving and paying closer attention to the exhaust, and that convinced me that I don't want to go louder than what I've got right now. The current muffler is an offset straight-thru design (2in 2out with a perforated central core) and I'm fine with the current volume, but I doubt much louder would be tolerable. I wonder how the RB universal would compare to a similar style Magnaflow or Borla in terms of sound characteristics as well as longevity. Ironically the RB universal muffler would probably be the cheapest option, yet also the longest lasting. Perhaps that says something...

Maxwedge

iTrader: (1)

I'd like to offer a different opinion on the sound of the RB system. I have the collected header full system on my 12a / Holley and it is loud A. F.. It is low-mile and all gaskets/hardware are good, but it just seems so, so loud inside the car (full interior). My wife can hear me cruising (3k rpm) when I turn onto our road from Main St, which is one mile away. I haven't turned the radio on since installing the exhaust, because there's no point.

That being said, when I put the new engine in I'll get RB's Street Port system. The systems are heavy and well made, and two pre-silencers Has to be quieter than one, right?

lwrobins

Rotary engine + Loud exhaust = headache

Benjamin4456

That's interesting, I don't think I've ever heard someone say that the RB system is loud. You have their new muffler right? I feel like you had a thread on that not too long ago. I wonder how much they changed with that new design - it looks like it's a completely different unit than the previous 'generation', perhaps they made it louder? A mile away seems surprisingly far, I don't even know if my car can be heard at 3k that far away - maybe in an area without many obstructions, but otherwise...? I can still hear my radio rather well even with my current exhaust, although perhaps that's just me listening to it loudly (driving around I listen at the same volume as when I use it as a work radio so... that's probably the case). I have a decibel meter somewhere, maybe I'll do a couple tests just for comparison sake. My current setup is definitely not the loudest around here by any stretch (I can't believe how loud some subaru drivers around here have theirs), so maybe it's not as crazy as I thought. I'll get some numbers at some point here.

There are definitely some exhausts I've heard around town that I could not deal with on a daily basis. I think part of the reason I can live with mine is that it doesn't drone too bad. The most annoying part by far is the buzzing sound that I hit at 3k. I many times try to shift below that just to avoid it, but then it puts me back down where I've got little power so it's really not ideal. I guess I'm really just looking for a good quality replacement while not changing the volume from current by much. Unfortunately my current muffler has no ID so I can't figure out what it is to compare to others, but I will say it's surprisingly small (I'll get a photo or two up here perhaps). Perhaps if anyone has a little time and access to a decibel meter they could check their exhaust volume at a few different rpms? Under load would be pretty hard to get a number on unless perhaps it was inside the car. Eh, just a thought. Thanks again for the input thus far.

yeti

iTrader: (1)

For intake I have weber 48 ida carb (which is loud on its own). For exhaust, Racing Beat header to Magnaflow cat, FC Racing Beat NA pre-silencer, and the new Racing Beat Power Pulse muffler. It's still plenty loud. I somehow managed set off a car alarm last week could have been coincidence though. I thought about getting the PR-Extreme but was afraid it would had been too loud.

Yeah the exhaust is a mess but considering it was straight pipe with a leak I have managed to quiet it down a good deal. I think the intake is now louder than the exhaust at least at idle and blipping the throttle.

rxtasy3

iTrader: (2)

i have the RB streetport system, which consists of road race header(not collected). dual presilencers, and primaflow muffler. it's way quieter than the other(same) system i have without the presilencers. yes these setups r heavy but they will out last the car.

Maxwedge

iTrader: (1)

Ben, I assume it's RB's "new" muffler. I bought the whole kit from them Nov '18, and not sure what the differences are.

It is insanely more loud than the stock exhaust it replaced. On startup the high idle (2000-ish) buzzes the windows on my house. It sounds great at warm idle, and might sound great to people as I drive past, but inside the car it's like being in a barrel with rocks and angry bees, rolling down a hill. Everyone else on the forum loves them, so maybe I just got a "special" muffler. IDK.

Also, my DD is a turbo Subie with full intake and full 3" turbo-back exhaust. No CAT or resonator, and straight-through exhaust. It is no-where near as loud as my RX.

j9fd3s

iTrader: (3)

i did a custom exhaust, its an RB header, into 2 glasspacks, into a 3" borla. its too loud (it does sound ok though), and its melting off of the car. it was also the same $$ as the RB system... so FML

Jeff20B

iTrader: (13)

My favorite rotary exhaust will always be the the RB SP system. It works well. In fact it works so well I've tried to emulate it in other rotary vehicles like the REPU. I've done three semi-long primary setups in those. I can't get the collector as far back as the RB unless I do some creative pipe work, but it seems ok at only 60 inches instead of 78.

I've studied the science behind why the RB SP works as well as it does. I know why it sounds as nice as it does. It is all in the physics at play here.

WANKfactor

iTrader: (1)

maybe your muffler got packed on a friday

lwrobins

Racing beat has changed the muffler on there street port exhaust system a few times. This is from 2017, V2 I believe. At that time racing beat told me they were having trouble with the supplier and were going back to in house manufacturing.

j9fd3s

iTrader: (3)

the original style mufflers were from Italy. they were black coated. there were a couple different tip styles over the years, there was an angled one, straight...

rwatson5651

iTrader: (5)

I just bought a complete system and was surprised to find this muffler with twin pipes into the muffler (like in Maxwedges picture) rather than it going into one pipe over the axle and then into the muffler (like in lrobins picture).

I called them for details and was told that this design was a result of complaints that the old style mufflers restriction hurt power on higher flowing engine setups like four port 13b racing motors, so this one was designed to be more free flowing and was consequently louder.

This has caused me to use this new muffler on my four port 13b that is occasionaly tracked, and put the quieter older style muffler from my track car on my daughter's mostly stock 12a car, hopefully it will not be too loud for her, and free up a little power on the track car. I hope its not too loud, will see.

Benjamin4456

Thanks everyone for all the posts - a lot of interesting info.

I got curious and decided to see how loud my exhaust really is - turns out that decibel meter I have actually is useful for once. While at the moment I have little to compare to, if anyone feels like getting some numbers on their setup as well I'd be grateful. There are mobile apps that can supposedly measure sound intensity, although I don't know how accurate they are. Anyway, here's some numbers.

Interior idle: 60dBA, 79dBC
Interior 2k (no load): 68dBA, 88dBC
Exterior idle ~24" from tailpipe: 80dBA, 96dBC

That's all the data I've got for now, although perhaps I'll eventually get some additional scenarios tested.

I also contacted RB, and given my setup, they suggested either their standard power pulse or the universal muffler (just talking mufflers at this point). They also said the the universal is free-er flowing than the power pulse and hence louder, although I don't know by how much. In doing some more looking around it seems that perhaps my car isn't as loud as I thought it might be, and if that's the case perhaps a generic (magnaflow for example) muffler would be a regrettable choice; just not sure... Choosing an exhaust is hard thing to do when you can't actually hear any for reference. As of now I think I'm pretty set on doing a 2.5" single system with an RB pre-silencer and a magnaflow cat, so really that just leaves the muffler. I feel as though the RB universal one would be a good bet, although I'm just a sucker for dual tips so, heck. If the latest revision RB power pulse has indeed changed significantly (which is what it sounds like might be the case) I might be interested in that, but I've never actually heard it. Videos of the older one always sound a little... buzzy? That's funny too because everyone seems to say that they aren't that, perhaps video's just don't convey it well?

Right now I've hit a brick wall of sorts. Without additional 'data' it's difficult to decide what path to take, particularly because each one is so different. Opinions are great, and I thank all of you for them, but they're opinions after all. I think the RB SP or any long primary system is out of the running for now, mostly because I have to get a cat in there somehow. Maybe later down the road I'll take another look at it, but not now. I also do find it interesting that RB no longer collects the SP system which I thought was one of the main benefits - collecting later that is. Anyhow, it looks like options are narrowed down to the normal power pulse, the RB universal muffler, or some other similar dual tip design (such as the Magnaflow I listed originally). Given past opinions (as in on the older version muffler) I am currently leaning away from the normal power pulse. I've never heard it in person, but in videos it always sounds so... different? It's seems like a combination of a deep buzz and whoosh if that makes any sense at all. I like the deep tone, but to me (again, I've only seen videos) they seem, oi, too refined? It's weird to say, but I think that might be it. I enjoy the raw sound of the rotary, think drag racing or something, but that's plenty too loud for a street car. Perhaps y'all can tell I'm a bit lost at this point - doesn't help that my car is only the second modified rotary I've ever seen up close. Maybe something in whatever I just wrote will remind someone of something, I don't know. Thanks for the advice thus far, feel free to keep chiming in.

j_tso

iTrader: (2)

The non-collected SP muffler surprises me as well. Uncollected pipes into the muffler is the same configuration as the stock 81-82 mufflers, supposedly the most free flowing OEM muffler.

Hopefully it's packed well enough. Over 10 years ago I bought the headers and SP presilencers, but used my stock 82 muffler since I figured OEM = quieter. It was loud and tinny, fart-can sounding. I completed the system with the RB muffler soon after that.

Jeff20B

iTrader: (13)

j_tso, I did the same thing about ten years ago and it had the same result.

Benjamin4456

So I've been talking with some folks at RB for the past couple days and learned some interesting things. First and foremost, the 'new' Power Pulse mufflers are technically a straight-thru design: "The PP design is single inlet – expansion chamber – 2 perforated pipes – dual tips." I found that interesting because I always thought the the previous generation Power Pulse mufflers were baffled. Perhaps that's why these are louder. I also found out that the over-axle section of their 83-85 muffler is a 60mm pipe, so that will work just fine with the rest of my system which is 2.5".

Getting to the point here, I think y'all and the folks at RB finally convinced me. I've liked the appearance of the new Power Pulse mufflers since they came out (not as much of a fan of the straight tip black can's back when those were still being sold), and the added convenience of all the mounting points, tips, and over-axle pipe already being done make the deal that much sweeter. With the other parts I was looking at I would have ended up paying a similar price anyhow, so it all works out. I'll be curious to find out what the new ones sound like - hopefully I don't get a unit that imitates "a barrel with rocks and angry bees, rolling down a hill" from the interior like Maxwedge.

As of now my planned setup is my current RB collected header, 1/8" wall 2.5" diameter pipe, an RB universal presilencer, Magnaflow cat, and an 83-85 Power Pulse muffler to finish it up. The thread might go dormant until I get my new exhaust parts in and then find time to install them, but when I finally do I'll be sure to update.

Thanks again for all the pointers and opinions.