Fundamental exhaust question...
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Fundamental exhaust question...
Hey,
Ok so I was thinking about exhausts... I have heard before, that there is no difference between a good 'true dual' exhaust and a good single exhaust that utilizes a Y pipe. Then why do people flock to the 'true' dual exhausts that are not really true since they utilize X pipes to balance flow.
Also for the Y pipe in the single exhaust, do you add the area from the smaller two pipes when determining the size of the larger single pipe.
2.5" initial piping => 4.9 area 4.9x2=9.8 9.8 area ~> 3.5" diameter
Assuming that my reasoning is correct, whats the difference between a 'true dual' that is 2.5" piping all the way back, compared to a single that is 2.5" to 3.5" single piping out the back? (besides the ability to brag considering the apparent prestige from having a true dual over a single)
Second question...
If there was restriction in the exhaust, where would it be it be less harmful? closer up around the Y pipe area, or further back near the muffler.
Ok so I was thinking about exhausts... I have heard before, that there is no difference between a good 'true dual' exhaust and a good single exhaust that utilizes a Y pipe. Then why do people flock to the 'true' dual exhausts that are not really true since they utilize X pipes to balance flow.
Also for the Y pipe in the single exhaust, do you add the area from the smaller two pipes when determining the size of the larger single pipe.
2.5" initial piping => 4.9 area 4.9x2=9.8 9.8 area ~> 3.5" diameter
Assuming that my reasoning is correct, whats the difference between a 'true dual' that is 2.5" piping all the way back, compared to a single that is 2.5" to 3.5" single piping out the back? (besides the ability to brag considering the apparent prestige from having a true dual over a single)
Second question...
If there was restriction in the exhaust, where would it be it be less harmful? closer up around the Y pipe area, or further back near the muffler.
#2
Injen does NOT have a x-pipe, so i can safely say it is a true dual exhaust.
The exhaust is just a personal thing, they make different sounds thats about it. Havin ridden in a bunch of different G's, i can only tell you that the powerband will be moved a little only when you have more mods than just an exhaust.
The exhaust is just a personal thing, they make different sounds thats about it. Havin ridden in a bunch of different G's, i can only tell you that the powerband will be moved a little only when you have more mods than just an exhaust.
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Originally Posted by Clean G 4D
Hey,
Ok so I was thinking about exhausts... I have heard before, that there is no difference between a good 'true dual' exhaust and a good single exhaust that utilizes a Y pipe. Then why do people flock to the 'true' dual exhausts that are not really true since they utilize X pipes to balance flow.
Also for the Y pipe in the single exhaust, do you add the area from the smaller two pipes when determining the size of the larger single pipe.
2.5" initial piping => 4.9 area 4.9x2=9.8 9.8 area ~> 3.5" diameter
Assuming that my reasoning is correct, whats the difference between a 'true dual' that is 2.5" piping all the way back, compared to a single that is 2.5" to 3.5" single piping out the back? (besides the ability to brag considering the apparent prestige from having a true dual over a single)
Second question...
If there was restriction in the exhaust, where would it be it be less harmful? closer up around the Y pipe area, or further back near the muffler.
Ok so I was thinking about exhausts... I have heard before, that there is no difference between a good 'true dual' exhaust and a good single exhaust that utilizes a Y pipe. Then why do people flock to the 'true' dual exhausts that are not really true since they utilize X pipes to balance flow.
Also for the Y pipe in the single exhaust, do you add the area from the smaller two pipes when determining the size of the larger single pipe.
2.5" initial piping => 4.9 area 4.9x2=9.8 9.8 area ~> 3.5" diameter
Assuming that my reasoning is correct, whats the difference between a 'true dual' that is 2.5" piping all the way back, compared to a single that is 2.5" to 3.5" single piping out the back? (besides the ability to brag considering the apparent prestige from having a true dual over a single)
Second question...
If there was restriction in the exhaust, where would it be it be less harmful? closer up around the Y pipe area, or further back near the muffler.
great question, anyone with knowledge please chime in, im interested to know about this as well
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Originally Posted by ISMSOLUTIONS
This is pretty easy all and has been discussed massively already.
X and H pipes are used in Dual system to balance and tune exhaust. Both banks of the engine do not fire and put out their gasses at the same pressure, so the X and H balance that and promote exhaust gas scavenging - VERY important.
Perforated X pipes are basically mufflers with X-pipes inside, you get the same X pipe result with further tunability of the overall sound.
X pipes are mainly for 6 Cyl engines and H's are used for V8's. The X pipes also increases HP by increasing efficiency of the system overall.
Taking a dual system and making it a Y-pipe is not dual - taking a dual system, balancing it, and keeping it dual, with dual mufflers all the way, is a dual system.
This is why...let me know if you need more...
X and H pipes are used in Dual system to balance and tune exhaust. Both banks of the engine do not fire and put out their gasses at the same pressure, so the X and H balance that and promote exhaust gas scavenging - VERY important.
Perforated X pipes are basically mufflers with X-pipes inside, you get the same X pipe result with further tunability of the overall sound.
X pipes are mainly for 6 Cyl engines and H's are used for V8's. The X pipes also increases HP by increasing efficiency of the system overall.
Taking a dual system and making it a Y-pipe is not dual - taking a dual system, balancing it, and keeping it dual, with dual mufflers all the way, is a dual system.
This is why...let me know if you need more...
I am already familiar with all the concepts discussed here http://www.nsxprime.com/FAQ/Miscella...austtheory.htm, and I understand how the X/Y pipes are necessary to promote efficient scavenging by aligning the pulse to draw out exhaust. My question regarding the two is, whats the difference? If you were to sync/balance the exhaust pressure with the X pipe, why split it back up again? Where is the gain as opposed to a single system that is also synced via Y pipe. Also, since the dual exhaust is bridged with the X pipe to balance pressure, what makes it true?
I still want answers/discussion on my other questions, is anyone wants to take a stab at them...
Originally Posted by Clean G 4D
Hey,
Ok so I was thinking about exhausts... I have heard before, that there is no difference between a good 'true dual' exhaust and a good single exhaust that utilizes a Y pipe. Then why do people flock to the 'true' dual exhausts that are not really true since they utilize X pipes to balance flow.
Also for the Y pipe in the single exhaust, do you add the area from the smaller two pipes when determining the size of the larger single pipe.
2.5" initial piping => 4.9 area 4.9x2=9.8 9.8 area ~> 3.5" diameter
Assuming that my reasoning is correct, whats the difference between a 'true dual' that is 2.5" piping all the way back, compared to a single that is 2.5" to 3.5" single piping out the back? (besides the ability to brag considering the apparent prestige from having a true dual over a single)
Second question...
If there was restriction in the exhaust, where would it be it be less harmful? closer up around the Y pipe area, or further back near the muffler.
Ok so I was thinking about exhausts... I have heard before, that there is no difference between a good 'true dual' exhaust and a good single exhaust that utilizes a Y pipe. Then why do people flock to the 'true' dual exhausts that are not really true since they utilize X pipes to balance flow.
Also for the Y pipe in the single exhaust, do you add the area from the smaller two pipes when determining the size of the larger single pipe.
2.5" initial piping => 4.9 area 4.9x2=9.8 9.8 area ~> 3.5" diameter
Assuming that my reasoning is correct, whats the difference between a 'true dual' that is 2.5" piping all the way back, compared to a single that is 2.5" to 3.5" single piping out the back? (besides the ability to brag considering the apparent prestige from having a true dual over a single)
Second question...
If there was restriction in the exhaust, where would it be it be less harmful? closer up around the Y pipe area, or further back near the muffler.
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^ not necessarily. If someone is knowledgable in this regard, then they would know the 'reasons' why there are differences, and why one would perform in a certain way. I am not asking for specific answers like 2.34576 whp at 5000rpm. I want the 'reasons'... why the true dual is 'true'? what the differences are between efficiency of X/Y pipe (are there any or is it a way to charge more for more piping and parts)?
*edit* The 'reasons' would be subject to testing to be proven, but I am only asking for the theory.
*edit* The 'reasons' would be subject to testing to be proven, but I am only asking for the theory.
Last edited by Clean G 4D; 10-03-2006 at 01:56 PM.
#10
Originally Posted by diablo1356
so what system is more efficient for street driving (power down low)...stock exhaust with minor bolt ons (intake, spacer, headers, HFC) or dual exhaust with the X pipe with the same bolt ons?
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From what I gather, there wouldnt be a difference between the two if the single exhaust goes along with my calculations earlier. The 3.5" single exhaust would handle the same amount of exhaust as the dual with two individual 2.5" pipes. I think the exhaust velocity would also be the same when set up this way.
#12
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3.5" exhaust is HUGE for a na application. Unless you have a big block 572!
I'm not sure you can get a Y with a 3.5" outlet anyway.
Yes, if you ran big downpipes from the Y into a 3.5" collector and ran the rest of the system 3.5", there would be a big loss of low end due the loss of exhaust velocity.
I'm not sure you can get a Y with a 3.5" outlet anyway.
Yes, if you ran big downpipes from the Y into a 3.5" collector and ran the rest of the system 3.5", there would be a big loss of low end due the loss of exhaust velocity.
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Originally Posted by Klubbheads
im guessing with intake, spacers, headers, HFCs with true dual like ISMSOLUTIONS mentioned, you aren't really going to lose low end and gain a lot, like 20 hp high end especially above 5k rpm. So with the mods u mentioned it is better to go with true dual with X-pipe. Without the mods stock or single piped exhaust is a good balance for power low and high end, but u will lose some power down low if u go true dual without any cat, header mods.
#14
Originally Posted by Clean G 4D
From what I gather, there wouldnt be a difference between the two if the single exhaust goes along with my calculations earlier. The 3.5" single exhaust would handle the same amount of exhaust as the dual with two individual 2.5" pipes. I think the exhaust velocity would also be the same when set up this way.
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Originally Posted by Jeff92se
3.5" exhaust is HUGE for a na application. Unless you have a big block 572!
I'm not sure you can get a Y with a 3.5" outlet anyway.
Yes, if you ran big downpipes from the Y into a 3.5" collector and ran the rest of the system 3.5", there would be a big loss of low end due the loss of exhaust velocity.
I'm not sure you can get a Y with a 3.5" outlet anyway.
Yes, if you ran big downpipes from the Y into a 3.5" collector and ran the rest of the system 3.5", there would be a big loss of low end due the loss of exhaust velocity.
You can try it too...
given:
2.5" piping = 1.25" radius
Area of circle = pi x (radius)^2
-add area of both pipes, then reverse the above equation to find diameter of larger pipe.
If someone knows how this is actually calculated, please chime in.