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RickBlaine
09-30-2015, 03:46 PM
Gents,

My original exhaust has had it. I need to replace it this week. A local muffler shop is quoting me $180 installed for everything behind the catalytic converter (includes resonator and muffler).

1) I searched and my understanding is that the stock exhaust size for a 1991 Nissan 240sx (with automatic transmission) is 2 1/4 inches outside diameter (o.d).
http://zilvia.net/f/showthread.php?t=77119

If that size is incorrect please let me know the correct size....

2) Catalytic converter delete: I want to temporarily install a test pipe in place of the original catalytic converter. Will this throw any engine codes in a 1991 model? The 02 sensor is "upstream"- so I don't think it will, but I am not the expert here.

3) To add a MagnaFlow catalytic converter later (universal one- not CARB compliant), which nuts and bolts (stainless) will be the least resistant to rust so I can install/remove the catalytic converter/test pipe?

4) Please note that the car is 100% stock, with 103,000 miles, and does not burn a drop of oil. I have no plans to modify THIS car.

5) I am older, and do not want to attract attention. I was actually pulled over yesterday because my exhaust gasket between the cat and the rear pipe blew out- making lots of noise. Next week I start getting ticketed- and I do NOT want one of those 4" coffee can exhausts that local youths all get.

I need your help please! Thank you!

ixfxi
09-30-2015, 04:10 PM
2.25 sounds right, its been ages since I had an NA 240SX. I recall at the time I upgraded to 2.5 inch and I had a Remus dual tip exhaust, I too wanted to look covert. Sounded OK, but overpriced muffler and crush piping didnt do much of anything for performance. Current setup with my SR is all 3.0 inch. I just yanked my 3" Magnaflow stainless steel cat and fab'ed up a stainless steel "test pipe" with flex section and wideband o2 port.

On an NA car, I really wouldnt advise being without a cat. It sounds shitty, it smells shitty. Unless you're turbo and blowing fireballs, keep the cat. Use all 304 stainless piping, flanges and fasteners - that will keep corrosion down to a minimum.

ps: I run an "angled" RSR GT2 coffee can exhaust, but... its powdercoated black. :-P

ps: I advise checking under the car to confirm your exhaust diameter. Use a caliper.

Matej
09-30-2015, 04:34 PM
The catalytic converter is there so polar bears do not starve.

Kingtal0n
09-30-2015, 05:13 PM
Just source another OEM exhaust system. The Factory exhaust on our cars is identical to the exhaust used on the JDM silvia- it will support 250rwhp with ease.

Absolutely no reason to use anything but on an N/A 2.4L engine

RickBlaine
09-30-2015, 05:32 PM
2.25 sounds right, its been ages since I had an NA 240SX. I recall at the time I upgraded to 2.5 inch and I had a Remus dual tip exhaust, I too wanted to look covert. Sounded OK, but overpriced muffler and crush piping didnt do much of anything for performance. Current setup with my SR is all 3.0 inch. I just yanked my 3" Magnaflow stainless steel cat and fab'ed up a stainless steel "test pipe" with flex section and wideband o2 port.

On an NA car, I really wouldnt advise being without a cat. It sounds shitty, it smells shitty. Unless you're turbo and blowing fireballs, keep the cat. Use all 304 stainless piping, flanges and fasteners - that will keep corrosion down to a minimum.

ps: I run an "angled" RSR GT2 coffee can exhaust, but... its powdercoated black. :-P

ps: I advise checking under the car to confirm your exhaust diameter. Use a caliper.

Thank you sir.

1) I will check diameter with a caliper (didn't even think of my caliper yet it is so obvious!) Just checked- the outside diameter of the exhaust pipe (just after the catalytic converter) is 2.25 inches.

2) I do remember that smell cars w/o a catalytic converter leave- it is not nice. The muffler shop has a cat- but it is a no name. I have a MagnaFlow coming in on Tuesday of next week. Thought I would test pipe it....maybe I'll just save a headache and get them to install their cat.

3) Thanks for tip on 304 stainless- I will have to ask what stuff they use. What do you mean by "crush"? Do you refer to crush vs. mandrel bending the pipe?

Any other advice or tips? I appreciate it!

RickBlaine
09-30-2015, 05:35 PM
Just source another OEM exhaust system. The Factory exhaust on our cars is identical to the exhaust used on the JDM silvia- it will support 250rwhp with ease.

Absolutely no reason to use anything but on an N/A 2.4L engine

Also an excellent idea.....There is a dude selling his used S13 exhaust (supposedly 80,000 miles on it)- but it is....used. If I check the integrity of the connections (gaskets and such) and it does not seem clogged, is $50 good to buy it? How much would you think a muffler shop would charge to drop the old and add the "new" S13 stock exhaust? I will call around in the a.m., but they are all closed now.

Thank you!

ixfxi
09-30-2015, 08:22 PM
Just source another OEM exhaust system. The Factory exhaust on our cars is identical to the exhaust used on the JDM silvia- it will support 250rwhp with ease. Absolutely no reason to use anything but on an N/A 2.4L engine

Also an excellent idea.....There is a dude selling his used S13 exhaust (supposedly 80,000 miles on it)- but it is....used.

The answer to the above is YES and NO.

Yes, technically you could just grab ANY stock S13 exhaust you find and install it, but then you are left with: a used exhaust. No glory in that, it just works. Performance and sound are, well... OE. However, you're still left with a janky 20+ year old exhaust thats mostly worn and rotten. And, heavy!

Now if none of that matters, then you step into the world of aftermarket. There ARE very high quality exhausts out there that will work great for NA *and* turbo, should you ever venture that route. Even if you dont care about performance, there's nothing wrong in my book with installing a nice quality component on your car. For example:

http://www.team-integra.net/forum/20-your-integra/87303-finally-got-my-rsr-exhaust-installed.html

^ RSR made, not sure if they still do, the EXMAG exhaust for our cars. This product was geared towards the sleeper crowd that want to blend in, but still have performance. The performance gains are found in nicely formed pipes known as mandrel bends. They are not crush formed (with kinks) like the stock exhausts or like muffler shop specials. I did not know or care about that many years ago, but now I do. Now I wouldnt waste my time with anything crush bent, and I very much like stainless steel - mandrel bent. This means buying something pre-made or fabricating it myself. With the wife's Miata I purchased a racing beat exhaust, mid pipe, headers, you name it. Beautiful construction.

So search away and I'm sure you'll find plenty. To keep the smells down I would advise running a cat. So basically, you need a cat-back setup.

Good luck

ixfxi
09-30-2015, 08:27 PM
http://wardsweb.org/cars/miata/exhaust/e07.jpg

Here is a side-by-side photo of a stock exhaust (miata, just an example) vs a stainless mandrel bent setup.

racepar1
09-30-2015, 08:53 PM
Thank you sir.

1) I will check diameter with a caliper (didn't even think of my caliper yet it is so obvious!) Just checked- the outside diameter of the exhaust pipe (just after the catalytic converter) is 2.25 inches.

2) I do remember that smell cars w/o a catalytic converter leave- it is not nice. The muffler shop has a cat- but it is a no name. I have a MagnaFlow coming in on Tuesday of next week. Thought I would test pipe it....maybe I'll just save a headache and get them to install their cat.

3) Thanks for tip on 304 stainless- I will have to ask what stuff they use. What do you mean by "crush"? Do you refer to crush vs. mandrel bending the pipe?

Any other advice or tips? I appreciate it!

I can for absolutely sure guarantee you that your muffler shop is NOT going to use mandrel bent 304 stainless. They will use crush bent mild steel piping, probably with the shittiest welds that could possible hold it together. $180 is way cheap. A nice stainless custom setup would run at least $500 and that's probably low. For your goals and needs a good condition stock setup would be ideal. HOWEVER, you do live in the rusty side of the country and finding a good one would likely be impossible.

As for the cat, why are you set on replacing it? Is there something wrong with it? If not it would be silly and useless to change it. Aftermarket cats suck ass, basically ALL of them. 9 times out of 10 you'll buy a new aftermarket cat and install it to pass smog. The next time you need to smog it (2 years later) it'll fail again. I prefer to run factory cats, even if they're used. I would LOVE to buy a brand new factory one, but the last time I priced one out it was $900 (my price, NOT retail) and there was only 1 left in the country. Since your car is a federal car running without a cat will not set a check engine light, BUT the EGR will not function. 240's have a backpressure transducer that will not apply vacuum to the EGR unless there is enough backpressure. Even brand new shitty aftermarket cats can sometimes cause this issue. CA cars have an EGR temp sensor to monitor EGR operation, federal cars do not.

RickBlaine
09-30-2015, 09:01 PM
THAT is a work of art! Thank you for posting that.

Bleakley
09-30-2015, 09:27 PM
I do have a stock 1992 exhaust. I've owned two s13's before this and was actually surprised how quiet it was - which is why I kept it stashed away in my storage unit. Car was from north Carolina so the exhaust def still has years left on it. If interested PM me.

ixfxi
09-30-2015, 11:31 PM
I can for absolutely sure guarantee you that your muffler shop is NOT going to use mandrel bent 304 stainless. They will use crush bent mild steel piping, probably with the shittiest welds that could possible hold it together. $180 is way cheap. A nice stainless custom setup would run at least $500 and that's probably low. For your goals and needs a good condition stock setup would be ideal. HOWEVER, you do live in the rusty side of the country and finding a good one would likely be impossible.

As for the cat, why are you set on replacing it? Is there something wrong with it? If not it would be silly and useless to change it. Aftermarket cats suck ass, basically ALL of them. 9 times out of 10 you'll buy a new aftermarket cat and install it to pass smog. The next time you need to smog it (2 years later) it'll fail again. I prefer to run factory cats, even if they're used. I would LOVE to buy a brand new factory one, but the last time I priced one out it was $900 (my price, NOT retail) and there was only 1 left in the country. Since your car is a federal car running without a cat will not set a check engine light, BUT the EGR will not function. 240's have a backpressure transducer that will not apply vacuum to the EGR unless there is enough backpressure. Even brand new shitty aftermarket cats can sometimes cause this issue. CA cars have an EGR temp sensor to monitor EGR operation, federal cars do not.

aaron is correct on a lot. costs for an SS setup can be high, very much so if its custom made. If they are pre-made however, it can be affordable. btw aaron, there are good muffler shops that make custom SS exhausts - i'm sure we agree though its pricey.

as for the cat, i ran the magnaflow (non CA type) and not only did I pass here in socal, i passed with my SR20DET, and I want to say not just once... i believe 2 times. most of the cats are ceramic-type, but they also sell more expensive metallic type cats. im sure they are pricey.

this thread is funny. reminds me of what forums USED to be like before the influx of fucking brain-dead ex-honda driving zombies we've had for the last 10 years.

Matej
10-01-2015, 12:24 AM
The HKS Sport appears to be a nice affordable low-key exhaust, despite being 3". I am not sure how loud/quiet it is behind a catalytic converter. Too bad HKS does not offer a 2.5" version with a resonator on the mid-pipe, but it still seems to be the most sensible exhaust available for those who want something in between the stock peashooter and an annoying cannon, since the aftermarket is mostly aimed at Hoonigans.

http://cdn6.frsport.com/images/detailed_images/21407_HKS_31013-BN002_FS01-01.jpg

racepar1
10-01-2015, 12:30 AM
The HKS Sport seems like a nice affordable low-key exhaust, despite being 3". It would be even better if HKS offered a 2.5" version with a resonator on the mid-pipe, but it still seems to be the most sensible new exhaust available today, since the aftermarket is mostly aimed at Hoonigans.

http://cdn6.frsport.com/images/detailed_images/21407_HKS_31013-BN002_FS01-01.jpg

Yeah, I've got a similar exhaust on my S13, RSR ex-mag. It is in NO WAY even REMOTELY close to being considered SORTA-KINDA quiet. My Apex N1 one-piece was actually quieter. But, like the OP, I got tired of the big ass canister hanging off the back of the car. I think I'm going to add a resonator to the ex-mag...

OP might wanna look into the BRM stuff...

http://www.brmexhaust.com/1989-1994-Nissan-240sx-Catback-Exhaust-p/s13-240sx.htm

Probably won't be super stock quiet, but it's a mandrel bent catback system with low-key looks. It's also available with 2.25, 2.5, or 3 inch piping. The price isn't that bad either...

e1_griego
10-01-2015, 12:31 AM
^Catless with an SR mine was pretty quiet just idling and cruising around, and sounds decent when you get on it but not quiet, I agree.

Not sure how it sounds on a KA, though I sold mine to a local kid with a KA. Should make him stop by and record it to share.

racepar1
10-01-2015, 12:38 AM
^Catless with an SR mine was pretty quiet just idling and cruising around, and sounds decent when you get on it but not quiet, I agree.

Not sure how it sounds on a KA, though I sold mine to a local kid with a KA. Should make him stop by and record it to share.

It's way louder on a KA. Not so bat at cruise/light load, but when you get on it it gets pretty damn loud. That's very typical though. EVERY exhaust is louder on a KA than an SR.

Matej
10-01-2015, 12:41 AM
All the old school OEM-looking exhausts were quiet. They would probably sell better now than they did back then.
Fujitsubo, Kakimoto, Nismo, old HKS, etc. I had an ancient twin-tip exhaust with 2.75" piping for a CA18DET that was quieter than stock on the KA, but I was never able to find out what brand it was.

e1_griego
10-01-2015, 12:49 AM
It's way louder on a KA. Not so bat at cruise/light load, but when you get on it it gets pretty damn loud. That's very typical though. EVERY exhaust is louder on a KA than an SR.

Yeah, fair. Hooray turbo mufflers.

I had some old school (what I think was) Kakimoto on my sohc back in the day and it was quiet and sounded decent. I paid like $150 for it used, and it was awesome. Big resonator and muffler.

ixfxi
10-01-2015, 02:34 AM
http://cdn6.frsport.com/images/detailed_images/21407_HKS_31013-BN002_FS01-01.jpg

Here is a dick tip for ya... (sorry, been listening to too much of the Maddox podcast)

you can easily take the above exhaust and have a resonator added to the mid-pipe.

Thats the one thing people under-estimate, the resonator. 3" piping is not really a big deal, though for NA I think 2.5-2.75 would be better. But a resonator. Install a large resonator and you'll be good to go.

Bleakley
10-01-2015, 05:38 AM
Thats the one thing people under-estimate, the resonator. 3" piping is not really a big deal, though for NA I think 2.5-2.75 would be better. But a resonator. Install a large resonator and you'll be good to go.

+1, exhaust with a resonator will almost always sound better than an exhaust without one.

slow40sx
10-01-2015, 08:22 AM
I went with an ISIS type-E on my daily 240, its very very quiet at idle like stock quiet and cruising it drones a bit but its not loud by any stretch, when you stomp on it its a little loud, not unbearably loud though, the police here are exhaust Nazi's and I've dailied this thing for 2 years 30 miles round trip to and from work everyday never been pulled over, the actual sound of it is ok. It doesn't sound particularly good. Although, I personally hate the sound of a KA. I might throw it on my SR 240 one day just to hear what it sounds like, but here's a pic of it for ya, its nicely designed, tucks up pretty nicely and its stainless steel so it will last, and if its too shiny for ya, you could always paint the muffler black, I was thinking about doing that actually


http://i65.photobucket.com/albums/h217/siksilviasx/BB6B43CF-858D-4C41-A398-4A906FADAE2F_zps9j7vngoj.jpg (http://s65.photobucket.com/user/siksilviasx/media/BB6B43CF-858D-4C41-A398-4A906FADAE2F_zps9j7vngoj.jpg.html)

Kingtal0n
10-02-2015, 06:08 PM
I run an OEM Exhaust with one of these
http://i9.photobucket.com/albums/a90/kingtal0n/Kingtal0ns_240sx_2/P1210052_zpskjeiuxib.jpg (http://s9.photobucket.com/user/kingtal0n/media/Kingtal0ns_240sx_2/P1210052_zpskjeiuxib.jpg.html)

^ ^

it posses a diagnostic feature as well as recreational.

Bleakley
10-02-2015, 07:03 PM
Kingalton, what is that? Can't really make it out.. Exhaust cutout/dump?
@slow40sx - I have an Apexi N1 Dual that I bought for the sound and my GOD does it hang low, looks Fricken stupid. Idk if it's the circuit sports downpipe I've got on there right now or what, but it needs fixed.

Kingtal0n
10-02-2015, 10:03 PM
Yes. I wanted one for years and finally did it, and it has been hands down the most fun modification I have ever made.

I really, really love to listen to the engine, as much as anybody else- except that I prefer to listen to what is really coming out of the engine before it goes through all the twisty turny sound-changing materials of an exhaust system.

Else, I prefer to listen to my radio, i.e. hear nothing from the engine whatsoever like the car is completely bone stock.
Both settings (loud and quiet) have diagnostic value. With an OEM noise level engine, I can hear every tick tock the engine makes to verify it's condition.
With the downpipe open I can hear the act of combustion/compression and hear all cylinders firing correctly with an even tone.


I must have my cake and eat it too!

slow40sx
10-03-2015, 10:31 PM
Kingalton, what is that? Can't really make it out.. Exhaust cutout/dump?
@slow40sx - I have an Apexi N1 Dual that I bought for the sound and my GOD does it hang low, looks Fricken stupid. Idk if it's the circuit sports downpipe I've got on there right now or what, but it needs fixed.

The first 240 I bought in 06 came with apexi dual N1 on it and it hung low as fuck too lol, I put hose clamps on the hangers to pull it up higher, still hung low as fuck, then I traded the car lol

Matej
10-04-2015, 04:13 AM
Both settings (loud and quiet) have diagnostic value. With an OEM noise level engine, I can hear every tick tock the engine makes to verify it's condition.
With the downpipe open I can hear the act of combustion/compression and hear all cylinders firing correctly with an even tone.
You should put a cutout on each cylinder so you can see the diagnostics.

Bleakley
10-04-2015, 01:18 PM
The first 240 I bought in 06 came with apexi dual N1 on it and it hung low as fuck too lol, I put hose clamps on the hangers to pull it up higher, still hung low as fuck, then I traded the car lol

So unfortunate... Was definitely looking to remedy the situation by somehow getting it to tuck in a little closer.

ixfxi
10-04-2015, 07:12 PM
You should put a cutout on each cylinder so you can see the diagnostics.

yes, and stick your eat on each cylinder to test compression and confirm proper mixture

Kingtal0n
10-04-2015, 08:05 PM
You should put a cutout on each cylinder so you can see the diagnostics.

you dare mock the value of this diagnostic approach :D


we should all run around with really loud cars so that we cannot hear our engine's internals. That makes more sense.

ixfxi
10-04-2015, 10:07 PM
you dare mock the value of this diagnostic approach :D


we should all run around with really loud cars so that we cannot hear our engine's internals. That makes more sense.

thats what exhaust silencers are for. that, or valved exhausts.

the dump pipe approach is OK but i dislike the added plumbing added to the system.

racepar1
10-06-2015, 12:25 AM
you dare mock the value of this diagnostic approach :D


we should all run around with really loud cars so that we cannot hear our engine's internals. That makes more sense.

That doesn't even make any sense. I have NEVER heard an exhaust loud enough to the point that you couldn't hear a knock or valvetrain noise. Maybe a top fuel dragster or something. As an inverse statement, I guess all racecars should have a quiet exhaust so they can hear the engine's "internals"...

:picardfp:

Kingtal0n
10-06-2015, 01:03 AM
That doesn't even make any sense. I have NEVER heard an exhaust loud enough to the point that you couldn't hear a knock or valvetrain noise. Maybe a top fuel dragster or something. As an inverse statement, I guess all racecars should have a quiet exhaust so they can hear the engine's "internals"...

:picardfp:

I suppose you never heard a built engine quieted down to street noise levels... they make a racket. Especially with forged pistons slapping around.

Where did I originally hear of this? why I believe it was 1998, I was reading a book by David Vizard, something along the lines of how to build horsepower, Im sure. The book mentioned several times about how noisy the insides of engines could be, reinforcing that mechanical noise is an issue, for example,

http://i9.photobucket.com/albums/a90/kingtal0n/1_zpspjtuw9y4.jpg (http://s9.photobucket.com/user/kingtal0n/media/1_zpspjtuw9y4.jpg.html)

There was a sentance that goes something like this, "anyone thats never heard a high performance engine quieted down to street noise levels..." and Ill never forget the impression it left on with me. What it says makes absolutely perfect sense, If you want to be able to diagnose the mechanical aspect of your engine, you can NOT be bothered to listen to the exhaust system. If you had the option of running the engine and listening to it through a loud exhaust tone, or simply turning it over with a tool (imagine you could spin the engine with the ignition off to several thousand RPM to listen to the mechanical parts without combustion getting in the way) I think you see what I am saying.

Besides all that, keep in mind my main excuse was recreation.
I can listen to my engine for the $28 it cost to purchase, and install my cutout to my arguably throw-away-able OEM exhaust system (no big loss if it falls apart, its OEM trash right?). thanks, that's all I really wanted. And it makes me sooo happy, puts a smile on my face for sure listening to the fire breathing dragon. Then I get a headache, close it off put the windows up and the A/C on and forget about it.

omgosh
10-06-2015, 01:15 PM
If you have the hood up and you're outside the car it doesnt really matter what exhaust you have, you will be able to hear the engine.

However, when driving down the road windows up, it is waay easier to hear wacky engine noises, pumps dying, etc, with a stock exhaust.

racepar1
10-07-2015, 12:29 AM
LOTS of words, mostly bullshit...

I should have known you would respond with an epic novel full of crap. You can quote whatever book you want. I am a professional technician and have been working on REAL racecars or my entire life. Your diagnostic argument is bullshit. If you know the car and know what it should sound like you can pick out an odd noise pretty easily, even with an obnoxious exhaust. You want a cutout so you can be loud and obnoxious when you choose, quiet and low key when you choose as well. It's that simple, nothing more. I think cutouts suck and would prefer to have an exhaust that's moderate all the time. Not for ANY "diagnostic" purposes, just because I don't like obnoxiously loud exhausts.

Bleakley
10-07-2015, 12:44 AM
To each, their own guys..

Matej
10-07-2015, 12:55 AM
you dare mock the value of this diagnostic approach :D


we should all run around with really loud cars so that we cannot hear our engine's internals. That makes more sense.
On the contrary, what I want is a decent flowing exhaust that is as quiet as possible.
My car will have a 2.5" OEM-looking exhaust with downturn tips, a mid-muffler, and a high-flow catalytic converter.
I know that some people love to play hot spec tuner with their car and flip a bunch of switches and adjust a bunch of knobs before every drive, but I just want something simple that will perform decently in any environment.

ixfxi
10-07-2015, 10:05 AM
You want a cutout so you can be loud and obnoxious when you choose, quiet and low key when you choose as well. It's that simple, nothing more.

I understand where Talon is going, but I dont agree either. With his setup, you have a junk stock exhaust for "majority of driving" and then a cutout for... well, for nothing. You open it up, its obnoxious, and probably wont be used much other than a drag race here or there.

I'm more for a proper exhaust. Regardless of how its done, just a nice exhaust. Nicely bent tubing, the works. If you want adjustability, thats what silencers are for OR multi-valve exhaust. I just installed on in a buddy's porsche and its real nice.

I dont understand what all this talk about loudness if for, isnt that what turbos are for? best silencers, imo.

Kingtal0n
10-07-2015, 07:15 PM
just because I don't like obnoxiously loud exhausts.

That is your personal preference. Mine is that I prefer not to hear anything while I commute in my daily driver, therefore, I require an OEM exhaust system, hands down no questions no other substitutions. I also require 350+rwhp making the cut-out absolutely essential. I have no other options... you might see this now?

If you know the car and know what it should sound like you can pick out an odd noise pretty easily,

Alright lets use this as an example.

Im coming to look at your car for sale. I've never seen it before, therefore, I do not know it. I have no clue what it "should sound like"

If the owner starts the car, and all I can hear is the noisy exhaust system, well I should like to ask him "sir, would you be so kind as to quiet the exhaust, so that I might listen to the engine for mysterious noises?"

now my device has a diagnostic value, in this example.

Again I want to point out, I added it for fun, thats it. And again, I can throw away my exhaust system and grab another one for... nearly free... at any time. If the reversibility, and affordability, are not fun inducing factors, well, I should like to know what other free/fun modifications I might make that are as strongly appreciated!

Kingtal0n
10-07-2015, 07:24 PM
I understand where Talon is going, but I dont agree either. With his setup, you have a junk stock exhaust for "majority of driving" and then a cutout for... well, for nothing. ]

So this is curious. The OEM exhaust system actually improves the performance of my car (it feels that way) for stock boost driving situations, over the cut-out, and comes OEM on the S14/S15 Silvia sr20det cars as well. I therefore feel that an OEM exhaust system is perfectly adequate and acceptable for power levels in the 250-280rwhp range on any engine, and not simply "junk".

People install an exhaust system for two big reasons.
1. noise
2. performance

In the case of performance, there is nothing like an open downpipe behind a reasonably sized turbocharger. This cut-out is useless to me now at stock boost levels, but when I install my gt2871r it will become priceless. I will not run an OEM exhaust system closed up behind an 2871r at 18psi of boost, no sir. It will desire something a bit more open to achieve 350~rwhp, I am sure of that. So in the first case, it is there in case I desire performance, provided I have the compressor to back it up.

In the case of noise, I would argue that an open downpipe is unreasonably loud, pointlessly loud in fact, this is true. With this in mind, I would also point out that I can operate the device partially closed, that is, with only a minor tone from the exhaust, at my discretion. It is not an OPEN/SHUT switch, but rather, a moving butterfly with an infinite selection of settings.

I have now shown that in both cases (noise and performance) the adjust ability of a proper cut-out system on an OEM exhaust can provide all of the benefits and noise scenarios that you might wish for. Indeed there have been plenty of times when a noisy vehicle next to me revs it's engine (or turns up its sound system) and I have been able to look over, and exceed that noise from below the drivers seat of my car with the flick of a switch, to the dismay of the other car's driver, only to pull away completely silent again, leaving them wondering wtf just happened.

Its all in good fun. Just happy to be alive and breathing, no need to get mad at the internetz

ixfxi
10-07-2015, 09:28 PM
Talon... post a photo of your undercarriage. I would like to see a better visual of your undercarriage.

racepar1
10-08-2015, 12:48 AM
Talon... post a photo of your undercarriage. I would like to see a better visual of your undercarriage.

Whoa there, how did we get from talking about exhausts to taking pictures of each other's undercarraiges? I'm not sure I'm comfortable with the direction that this thread is going in...

:keke:

Talon, there you go snipping tiny pieces of a post off and writing responses to them. Posts are meant to be taken of the context of the entire post, not just the tiny piece you don't like. If you're looking at a car and you are not capable of picking out noises that don't belong, then maybe you should bring a buddy that knows what he's doing. Are we listening for noises with our ears directly beyond the exhaust tip? I would pop the hood and listen from there. If I heard a noise that I didn't like I would bust out the stethoscope and pin point it. With our paper thin firewalls you can hear then engine louder than you can hear the exhaust in the cabin. Odd noises aren't hard to pick out. Most often that odd noise is accompanied by a vibration. If you're an actual good driver you can pick up that vibration through the steering wheel, floorpan, and seats. If you're REALLY good you can pick out the area of the car that the vibration is coming from based on where and when you feel the vibration the most. Your argument is invalid...

ixfxi
10-08-2015, 10:44 AM
Whoa there, how did we get from talking about exhausts to taking pictures of each other's undercarraiges? I'm not sure I'm comfortable with the direction that this thread is going in...

haha

the problem is, we can go back and fourth trying to convince each other than one method is better than the other. in the end, i want to see what is attached to the bottom of this dudes car. in my head, i visualize a stock exhaust system with a cutout. nothing special about that. but maybe i am missing something.

i've never met a good mechanic who has trouble diagnosing a car that is too loud. either you know the sounds or you dont. aron, obviously you are a mechanic and know your shit. im just some gunslinging hobbyist/tuner but many of my mechanic friends ask me advice, so... in the end, we all rely on each other for help. but, there are plenty of less skilled individuals on forums. the miata forums is proof. most of the posts there are written by people who think the solution to every problem is changing plug wires and "seafoam treatment" - these people dont know their ass from their elbow. but hey, just because its a community doesnt mean its a community of professional mechanics. even mechanics dont fully understand all of the aspects of a car.

anyway. fuck the stock exhaust.

Kingtal0n
10-08-2015, 01:40 PM
Whoa there, how did we get from talking about exhausts to taking pictures of each other's undercarraiges? I'm not sure I'm comfortable with the direction that this thread is going in...

:keke:

Talon, there you go snipping tiny pieces of a post off and writing responses to them. Posts are meant to be taken of the context of the entire post, not just the tiny piece you don't like. If you're looking at a car and you are not capable of picking out noises that don't belong, then maybe you should bring a buddy that knows what he's doing. Are we listening for noises with our ears directly beyond the exhaust tip? I would pop the hood and listen from there. If I heard a noise that I didn't like I would bust out the stethoscope and pin point it. With our paper thin firewalls you can hear then engine louder than you can hear the exhaust in the cabin. Odd noises aren't hard to pick out. Most often that odd noise is accompanied by a vibration. If you're an actual good driver you can pick up that vibration through the steering wheel, floorpan, and seats. If you're REALLY good you can pick out the area of the car that the vibration is coming from based on where and when you feel the vibration the most. Your argument is invalid...

Ah, I see the reason for your confusion. I am here comparing all vehicles on the planet earth, including engines in cruise ships, or space ships, that is to say that the less the act of combustion interferes with your audible appraisal of any particular engine, the easier it will be to identify mechanical noise emitted. Since this applies to all forms of engines that utilize an explosive force to drive a surface, well it also applies to a 240sx. Just because you are able to overcome these difficulties (or assume that you are able to without measuring differences) does not make it any less true.

Kingtal0n
10-08-2015, 01:58 PM
haha

the problem is, we can go back and fourth trying to convince each other than one method is better than the other.


I do not think anybody claimed what was better. Only we have been mentioning our preferences.

I do not mind exhaust systems and changing the tone of the exhaust. In fact I would change my exhaust system every week for months using whatever was available to me, heres a picture I found of the corner where I would select a new exhaust each week that came from Japan while it was waiting for someone to buy it here in the USA.
http://i9.photobucket.com/albums/a90/kingtal0n/1995_240sx/seeit_zpsafpgtwdk.jpg (http://s9.photobucket.com/user/kingtal0n/media/1995_240sx/seeit_zpsafpgtwdk.jpg.html)

My friend has a shop where things like this are possible, and so I have been able to try many different types of exhausts over the last 10 years, and have been spoiled. Perhaps that is why I have opted for this OEM/cutout method, since it delivers a full minimal-adjusted dosage of the raw noise this engine is capable of making, a racket to some but sweet music to my ears. Another reason I do not have a trendy exhaust system is because I am a poor college student, and just because I can barrow them does not mean I get to keep for free!

racepar1
10-08-2015, 11:50 PM
Ah, I see the reason for your confusion. I am here comparing all vehicles on the planet earth, including engines in cruise ships, or space ships, that is to say that the less the act of combustion interferes with your audible appraisal of any particular engine, the easier it will be to identify mechanical noise emitted. Since this applies to all forms of engines that utilize an explosive force to drive a surface, well it also applies to a 240sx. Just because you are able to overcome these difficulties (or assume that you are able to without measuring differences) does not make it any less true.

I am using a 240sx as an example because we all understand it. This example also relates directly to your claim as you own a 240sx. As Mike said, I have NEVER met a GOOD mechanic that cannot diagnose an engine noise due to a loud exhaust. The noises are coming from opposite ends of the car, it's really pretty simple to distinguish between them. And yes I do know that some cars have the engines in the back, however that engine is between you and the exhaust noise, also not difficult to distinguish the difference. I understand why you would want a quiet exhaust, I am just saying the diagnostic argument is invalid. I know, you read it in some random book so it must be true, just like everything that's posted on the internet...

Matej
10-09-2015, 12:28 AM
In fact I would change my exhaust system every week for months using whatever was available to me, heres a picture I found of the corner where I would select a new exhaust each week that came from Japan while it was waiting for someone to buy it here in the USA.

That sounds like a pretty rotten business practice.

Kingtal0n
10-09-2015, 01:06 AM
That sounds like a pretty rotten business practice.

Right, because used exhaust systems hanging on a shelf are worth more than a used exhaust system on someone's car. Or using a used exhaust system somehow uses it more when its in the USA. Trying to figure out your angle or reasoning behind this. In fact every car we got instantly acquired an off the shelf used exhaust system- might as well put them to work.

Maybe you'd like to clarify how using a used exhaust system here in the USA somehow makes it worth less for the next guy? Heck I just sold the very clean, very well cared for Apexi GT-Spec exhaust off my car to somebody who was very happy to listen to it on my car before he bought it off me. Would have been worth more on a shelf in the back of the shop? Don't think so!

http://i9.photobucket.com/albums/a90/kingtal0n/Kingtal0ns_240sx_2/P1200166_zpsx0pj7jci.jpg (http://s9.photobucket.com/user/kingtal0n/media/Kingtal0ns_240sx_2/P1200166_zpsx0pj7jci.jpg.html)

It was a great system. In fact I feel like the car had more on the highway in 5th with this system than it does now. Although I've been through a clutch and a set of cams so my comparison might have been skewed a little.

Kingtal0n
10-09-2015, 01:12 AM
I am using a 240sx as an example because we all understand it. This example also relates directly to your claim as you own a 240sx. As Mike said, I have NEVER met a GOOD mechanic that cannot diagnose an engine noise due to a loud exhaust. The noises are coming from opposite ends of the car, it's really pretty simple to distinguish between them. And yes I do know that some cars have the engines in the back, however that engine is between you and the exhaust noise, also not difficult to distinguish the difference. I understand why you would want a quiet exhaust, I am just saying the diagnostic argument is invalid. I know, you read it in some random book so it must be true, just like everything that's posted on the internet...

This isn't about being a good mechanic. This is about the fact that gasoline explosions make noise, and that noise can hide other noises. You might be unaware of them (because you can't hear them). I am sure you understand how this fact is the basis of my statement.

Yeah I can tell if my engine is sick just by listening to it run- that doesn't mean everybody can.

Matej
10-09-2015, 01:50 AM
Right, because used exhaust systems hanging on a shelf are worth more than a used exhaust system on someone's car. Or using a used exhaust system somehow uses it more when its in the USA. Trying to figure out your angle or reasoning behind this. In fact every car we got instantly acquired an off the shelf used exhaust system- might as well put them to work.
Not sure how other people feel, but I would not be happy if I found out that the shop owner lets his buddies play dress up with the parts before selling them to me. I realize they already come used from Japan, but after learning this, I would endlessly wonder which of the scrapes and scuffs and bolt marks were on it completely unnecessarily thanks to you, because I am quite OCD about such things.

It is one thing to buy a used item from a private seller who had it for his own personal use, but it is another when a business sells you a used part that someone else used even more in between the time it was listed for sale with pictures and the time I purchased it.

Maybe they are listed/photographed for sale only after you have had your joyride with them to fairly represent the current condition, and maybe they are just cheap throw-away exhausts that are not even posted online and are just there for people to come rummage through in person, but now how do I know you do not do the same thing with other parts as well, such as wheels, aero, turbos, and such?
Either way, you are not doing your friend any favors by bragging online that you get your pick at the parts from his shop before he sells them.


Maybe you'd like to clarify how using a used exhaust system here in the USA somehow makes it worth less for the next guy? Heck I just sold the very clean, very well cared for Apexi GT-Spec exhaust off my car to somebody who was very happy to listen to it on my car before he bought it off me. Would have been worth more on a shelf in the back of the shop? Don't think so!
It is like buying a cool vintage coat online and the UPS guy comes wearing it to the door, because you know, it was already used anyway. Plus I probably wanted to see how it looks on someone else.

Kingtal0n
10-09-2015, 03:08 AM
Nay, all cars that come to the shop for shop use/sale get an exhaust off the shelf. They dont sit there lookin' pretty, easier to sell them on a car, or with the car, etc... You must not own a shop that builds cars I guess.

I can appreciate your concern over used JDM parts but when you own 100+ copies of various exhaust system it really doesn't matter which car gets which system. At some point we just started taking them for granted, like lemmings. Same thing with wheels, tires gone? Whats on the shelf? Yeah give me those Ill wear them out.

racepar1
10-10-2015, 12:21 AM
Kingtal0n is always right, no matter what...

:ugh:

Must have read that in a book too...

mewantkouki
10-10-2015, 01:41 AM
A screenshot of kingtal0n's organic chemistry homework would make this thread complete.

ixfxi
10-10-2015, 02:07 AM
Kingtal0n is always right, no matter what...

:ugh:

Must have read that in a book too...

hes so gaddamn smug

and i never understand his technical discussions

confusing, talon is

S14kouki805
10-10-2015, 09:56 AM
Why the fuck did I just read this entire thread? I want my 30min back

Kingtal0n
10-10-2015, 10:57 AM
This be da correction section for drinkin, smokin', and wastin' tiem

http://i9.photobucket.com/albums/a90/kingtal0n/Camaro_Days/Body_work/DVC02150_zps4rrr3ewu.jpg (http://s9.photobucket.com/user/kingtal0n/media/Camaro_Days/Body_work/DVC02150_zps4rrr3ewu.jpg.html)

Now back to work