08-18-2014, 03:13 AM (This post was last modified: 08-18-2014, 03:17 AM by cornflakes.)
Hey guys, I'm just curious about a little something.
I bought a used car and the car normally has just one exhaust tip on the left side (stock models), and mine is still stock but the previous owner looks like they made a dual pipe via welding another piping to the main pipe just BEFORE it enters the muffler. So instead of having one exhaust tip on the left side, I have another exhaust tip on the right side giving it that dual exhaust appearance but really it's still just a single pipe.
Now this extension pipe that goes to the right side, near the exhaust tip inside the piping is a ELECTRONIC VALVE. It can open and close with a push of a button.
I keep the button on so that the valve is closed, less noise but still louder than stock. But if I release the button, the valve opens on the right side and then it gets really loud.
The car is stock, it's not a special aftermarket catback or muffler or even larger piping. It's just a welded on extension pipe that goes to the right side and has an electronic valve that opens and closes for sound effect.
All I want to know is WHY does it make a louder noise? Can someone explain the physics or mechanics of how simply welding on another pipe (before the muffler) to extend out to the right side rear of the car makes the car sound much louder than without it?
Is it because the newly extended welded pipe has no muffler? The left side has a muffler and then the exhaust tip but the right side is just piping.
I'm just really curious as to where the noise is coming from and how does it make that noise?
Here's a pic that might help show you what I mean:
sorry, actually the extended muffler that goes to the right side is welded into the muffler on the left side. The main piping (thinner one) also goes into the muffler..that's the original piping. The newer extension one looks like it's a bit bigger in diameter maybe a 2.5"? and the stock looks smaller like 2".
(08-18-2014, 03:13 AM)cornflakes Wrote: Hey guys, I'm just curious about a little something.
I bought a used car and the car normally has just one exhaust tip on the left side (stock models), and mine is still stock but the previous owner looks like they made a dual pipe via welding another piping to the main pipe just BEFORE it enters the muffler. So instead of having one exhaust tip on the left side, I have another exhaust tip on the right side giving it that dual exhaust appearance but really it's still just a single pipe.
Now this extension pipe that goes to the right side, near the exhaust tip inside the piping is a ELECTRONIC VALVE. It can open and close with a push of a button.
I keep the button on so that the valve is closed, less noise but still louder than stock. But if I release the button, the valve opens on the right side and then it gets really loud.
The car is stock, it's not a special aftermarket catback or muffler or even larger piping. It's just a welded on extension pipe that goes to the right side and has an electronic valve that opens and closes for sound effect.
All I want to know is WHY does it make a louder noise? Can someone explain the physics or mechanics of how simply welding on another pipe (before the muffler) to extend out to the right side rear of the car makes the car sound much louder than without it?
Is it because the newly extended welded pipe has no muffler? The left side has a muffler and then the exhaust tip but the right side is just piping.
I'm just really curious as to where the noise is coming from and how does it make that noise?
sorry, actually the extended muffler that goes to the right side is welded into the muffler on the left side. The main piping (thinner one) also goes into the muffler..that's the original piping. The newer extension one looks like it's a bit bigger in diameter maybe a 2.5"? and the stock looks smaller like 2".
If the new pipe, when the valve is activated, allows the exhaust flow to bypass one of the mufflers/resonators, that would explain the louder noise.
2008 Fusion SEL MTX - DD1 * 2009 Fusion SEL - DD2 * 2007 Focus ZXW - R*I*P * 2004 Focus ZTW CD Silver - sold * 2004 Focus ZTW Black - sold * 2003 Focus ZTW Black - sold * 2001 Focus ZTW Gold - sold * 2000 Focus SE Wagon (ZTW option) - Black - sold * 2000 Focus SE Wagon (ZTW option) - Gold R*I*P
2003 Focus ZX5 infra-red Track Rat - R*I*P
2003 ZX5 CD Silver Track Rat - retired, but still in the driveway
New track rat: 2000 ZX3, Atlantic Blue * JRSC with lots more to come
(08-18-2014, 03:13 AM)cornflakes Wrote: Hey guys, I'm just curious about a little something.
I bought a used car and the car normally has just one exhaust tip on the left side (stock models), and mine is still stock but the previous owner looks like they made a dual pipe via welding another piping to the main pipe just BEFORE it enters the muffler. So instead of having one exhaust tip on the left side, I have another exhaust tip on the right side giving it that dual exhaust appearance but really it's still just a single pipe.
Now this extension pipe that goes to the right side, near the exhaust tip inside the piping is a ELECTRONIC VALVE. It can open and close with a push of a button.
I keep the button on so that the valve is closed, less noise but still louder than stock. But if I release the button, the valve opens on the right side and then it gets really loud.
The car is stock, it's not a special aftermarket catback or muffler or even larger piping. It's just a welded on extension pipe that goes to the right side and has an electronic valve that opens and closes for sound effect.
All I want to know is WHY does it make a louder noise? Can someone explain the physics or mechanics of how simply welding on another pipe (before the muffler) to extend out to the right side rear of the car makes the car sound much louder than without it?
Is it because the newly extended welded pipe has no muffler? The left side has a muffler and then the exhaust tip but the right side is just piping.
I'm just really curious as to where the noise is coming from and how does it make that noise?
sorry, actually the extended muffler that goes to the right side is welded into the muffler on the left side. The main piping (thinner one) also goes into the muffler..that's the original piping. The newer extension one looks like it's a bit bigger in diameter maybe a 2.5"? and the stock looks smaller like 2".
If the new pipe, when the valve is activated, allows the exhaust flow to bypass one of the mufflers/resonators, that would explain the louder noise.
So then the extra noise is coming from only the right side of the piping?
I just don't understand still the science behind why something gets LOUDER just because one adds a 2nd piping.
It's like if I was screaming through one of those towel paper cardboard cylinders, if I were to add a 2nd towel paper cardboard, I don't know how the 2nd towel paper cardboard roll acts like a microphone and amplifies my voice.
So if I decided to weld on a 2nd muffler to 2nd piping extension, I guess that would diminish the sound?
its louder because he added the pipe BEFORE the MUFFLER. if it was after then it would sound the same as stock .. a muffler muffles the sound, yes it makes that much of a difference
2000 dark violet pearl zx3: eagle rods, je pistons, fidanza cam gears, arp studs, ford racing highlift valve springs, svt front/rear disc conversion, prothane total kit, fc 65mm throttle body Tial gt3071r, tial mvs wastegate, tial Q bov, top speed "street" manifold,down pipe and dump tube, greddy boost controller, siemens deka #61 injectorz, stage 4 bully clutch way to much more to list Instagram @o_so_slo
Think of it this way - you don't really have a dual exhaust - what you have is two single exhausts, only one of which is used at any given time, depending on the position of the valve.
With the valve closed, the exhaust is routed through the side with the muffler - and so the sound is, well, muffled and therefore quiet.
With the valve open, the exhaust is routed through the side without the muffler, and therefore is louder.
2008 Fusion SEL MTX - DD1 * 2009 Fusion SEL - DD2 * 2007 Focus ZXW - R*I*P * 2004 Focus ZTW CD Silver - sold * 2004 Focus ZTW Black - sold * 2003 Focus ZTW Black - sold * 2001 Focus ZTW Gold - sold * 2000 Focus SE Wagon (ZTW option) - Black - sold * 2000 Focus SE Wagon (ZTW option) - Gold R*I*P
2003 Focus ZX5 infra-red Track Rat - R*I*P
2003 ZX5 CD Silver Track Rat - retired, but still in the driveway
New track rat: 2000 ZX3, Atlantic Blue * JRSC with lots more to come
08-19-2014, 02:28 AM (This post was last modified: 08-19-2014, 02:45 AM by cornflakes.)
(08-18-2014, 10:52 PM)ZTWsquared Wrote: Think of it this way - you don't really have a dual exhaust - what you have is two single exhausts, only one of which is used at any given time, depending on the position of the valve.
With the valve closed, the exhaust is routed through the side with the muffler - and so the sound is, well, muffled and therefore quiet.
With the valve open, the exhaust is routed through the side without the muffler, and therefore is louder.
Agreed, and that's totally right. Actually, the 2nd piping is not welded on BEFORE the muffler. I'll have to take a pic again and show, but it's welded into the muffler along with the original pipe.
So the 2nd extension pipe is coming out of that muffler also. I just wish I could study the science behind how it works. Also, when the valve is closed, the left side that goes through the muffler is still pretty loud. I always leave it closed anyways because it's REALLY LOUD when i open the valve, although it sounds very nice at idle or low rpms.
Why does the left side still sound loud even when the valve is closed and so it's running through the original piping and muffler.
Is a bit of the sound still resonating from the 2nd pipe even though the valve is closed? When I said that it's quieter, I meant comparatively to the when the valve is open. It's still A LOT louder than stock even with the valve closed. It's just a stock muffler and stock piping....again...is this ALL due to the 2nd extension piping alone?
It's quite interesting.
Here's a short clip i took of driveby when driving with valve closed and then open. Valve closed and open
from looking as the picture more closely I don't even see a resonator on your car. if that's the case that would make it that much more louder, even with a muffler - and a small one at that
2000 dark violet pearl zx3: eagle rods, je pistons, fidanza cam gears, arp studs, ford racing highlift valve springs, svt front/rear disc conversion, prothane total kit, fc 65mm throttle body Tial gt3071r, tial mvs wastegate, tial Q bov, top speed "street" manifold,down pipe and dump tube, greddy boost controller, siemens deka #61 injectorz, stage 4 bully clutch way to much more to list Instagram @o_so_slo
08-19-2014, 11:50 AM (This post was last modified: 08-19-2014, 12:01 PM by cornflakes.)
Hmm, I forgot to see if there is a resonator. Should be. It's usually located in the middle to front area right? Yeah, from my pictures u can't see it since it cuts off around the middle. I'll have to check it again...with all the rain lately and no jack stand it's a PITA to get under there and have a good look.
i also thought this might be what it is
It's still a single exhaust system but when it comes out of the muffler, it splits into a dual exhaust.
Not a true dual exhaust but the more I think about it, I think that's what my car has. The only reason
why it looks much different is because my car is so small it has very little space underneath that even
the stock muffler has to be position sideways. So the previous owner actually did the dual exhaust from
the muffler, which explains why the 2nd pipe that goes to the right side of the car is coming out of the muffler
as well and NOT welded on to the original pipe BEFORE the muffler.
I wonder how much of a difference in noise this makes comparing a system that has a 2nd pipe welded BEFORE the muffler entrance vs a system that has a single muffler with 2 exhaust pipes coming out of it.
just another example: http://www.angieslist.com/files/dual_exhaust.jpg
I think it's the same idea as what i have? Picture my muffler in the center and then 2 pipes coming out of it.
The only difference is since mine has no space under the body, it has to stay in it's regular location but 2 pipes
are still coming out of my muffler. Hmm.
the resonator should be located where you can see the heat shield in the tunnel. looks like it was removed
2000 dark violet pearl zx3: eagle rods, je pistons, fidanza cam gears, arp studs, ford racing highlift valve springs, svt front/rear disc conversion, prothane total kit, fc 65mm throttle body Tial gt3071r, tial mvs wastegate, tial Q bov, top speed "street" manifold,down pipe and dump tube, greddy boost controller, siemens deka #61 injectorz, stage 4 bully clutch way to much more to list Instagram @o_so_slo
08-19-2014, 10:20 PM (This post was last modified: 08-19-2014, 10:33 PM by ZTWsquared.)
If it was a true dual exhaust (even just two outlets coming from the muffler) there wouldn't be any use for a by-pass valve. The only way that valve can cause the exhaust to be louder, is if it is allowing the exhaust to go straight to atmosphere and not through the muffler - or at least through less of the muffler.
And depending on the configuration of the baffles inside the muffler, that can still be the case even if the second pipe is coming off the muffler.
And yeah - the pic seems pretty clear all the way to the front of the car - no resonator - just the one muffler at the back.
Thanks, couldn't get the mp3 file to play as the geocities site looks like it's gone, but the photo sure did look the same! That's what I think mine is, one muffler but there's 2 pipe coming out of it.
Do you think it's possible that when I open the valve, there is another valve somewhere that shuts off or closes the left pipe/tubing? Or when I open the valve, does the exhaust then simply travel through both pipes then?
Ok, when I was at the shop again to get my new spoiler installed, I saw underneath the car again and the resonator is definitely gone. A straight pipe was welded in its place. That's probably what was making most of the noise, and not the 2nd welded on pipe with the valve in it.
Makes sense now. That's why I thought it was weird how a simply 2nd pipe could make so much noise. It's not really the pipe. It's the fact there's no resonator and the muffler side will still be loud but it at least makes it "less" loud. But then when the valve on the right side opens up, it's directly going out without any resonator and muffler, that's why it's so loud.
All this time, I thought there was some weird physics involved in adding a 2nd exhaust pipe that was behind the LOUD noise. I knew that couldn't be right.
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