Help me decide: Straight pipe or high flow cat?
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Help me decide: Straight pipe or high flow cat?
engine is 96 OBD2 H22a1. i already have AEM CAI and WS2 catback. Now i have ordered the megan header and plan to do the collector mod. I realize that to actually feel some gains something has to be done with the stock cat. I want to stay quiet as possible which is why i bought the WS2. Which would be best for my setup and would i need to convert to OBD1 to use a test pipe? im afraid a testpipe would ruin my quiet setup...
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I suggest keeping the cat, largely b/c im a supporter of f'ing up the environment as little as possible.
As far as a test pipe ruining your setup I think a resonator would fix that prob, but like I said, im against getting rid of cats. As far as your question goes about the test pipe and converting to OBDI I think your right.
When I do my exhaust setup over the summer I plan to get a 2.5"-3" cat (to allow for a large rate of flow) then to a 3" pipe exiting thru a 3"N1. ITs gonna be kinda loud and i hope the cat will get rid of some of the raspyness, if not ill be putting in a resonator.
As far as a test pipe ruining your setup I think a resonator would fix that prob, but like I said, im against getting rid of cats. As far as your question goes about the test pipe and converting to OBDI I think your right.
When I do my exhaust setup over the summer I plan to get a 2.5"-3" cat (to allow for a large rate of flow) then to a 3" pipe exiting thru a 3"N1. ITs gonna be kinda loud and i hope the cat will get rid of some of the raspyness, if not ill be putting in a resonator.
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Re: (KB96VTEC)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by KB96VTEC »</TD></TR><TR><TD CLASS="quote">whats the difference between a testpipe and a resonator?</TD></TR></TABLE>
Testpipe is a catalytic system eliminator IIRC. Resonator is a large tube larger in diameter than the exhaust pipe that will baffle a lot of the noise.
Testpipe is a catalytic system eliminator IIRC. Resonator is a large tube larger in diameter than the exhaust pipe that will baffle a lot of the noise.
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Yea, what he said. A test pipe is basically just a piece of pipe that you bolt up to ur exhaust in place of the cat. A resonator is a tube (usually larger in diameter than ur exhaust piping) that will help cancel out some of the high freq. sound waves.
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Re: (LudeBehavi0r)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by LudeBehavi0r »</TD></TR><TR><TD CLASS="quote">Yea, what he said. A test pipe is basically just a piece of pipe that you bolt up to ur exhaust in place of the cat. A resonator is a tube (usually larger in diameter than ur exhaust piping) that will help cancel out some of the high freq. sound waves.</TD></TR></TABLE>
Close maacus....the resonator actually cancels the higher amplitude waves. Higher amplitude=louder.
The reason it does that is because when they're flowing through the pipe they have nowhere to go, but when they hit the resonator, the holes in the pipe allow the wave to flow up and down more, and when they hit the steel wool once they get out of the holes in the pipe, they die out.
Keep in mind, these are our version of high flow "resonators"....they're honestly just straight through mufflers, resonators in their true form are much more restrictive, they involve sound waves cancelling each other.
Close maacus....the resonator actually cancels the higher amplitude waves. Higher amplitude=louder.
The reason it does that is because when they're flowing through the pipe they have nowhere to go, but when they hit the resonator, the holes in the pipe allow the wave to flow up and down more, and when they hit the steel wool once they get out of the holes in the pipe, they die out.
Keep in mind, these are our version of high flow "resonators"....they're honestly just straight through mufflers, resonators in their true form are much more restrictive, they involve sound waves cancelling each other.
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Re: (mgags7)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mgags7 »</TD></TR><TR><TD CLASS="quote">
Close maacus....the resonator actually cancels the higher amplitude waves. Higher amplitude=louder.
The reason it does that is because when they're flowing through the pipe they have nowhere to go, but when they hit the resonator, the holes in the pipe allow the wave to flow up and down more, and when they hit the steel wool once they get out of the holes in the pipe, they die out.
Keep in mind, these are our version of high flow "resonators"....they're honestly just straight through mufflers, resonators in their true form are much more restrictive, they involve sound waves cancelling each other.</TD></TR></TABLE>
Actualy ur wrong. Freq is the amt of space between the peaks of the sound waves and amplitude is how high/low the peaks are. Higher FREQ means more energy which equals louder. Low frequency (low energy) sound waves are the deeper tones you hear and are the ones created by the resonator. http://en.wikipedia.org/wiki/Frequency
My understanding of a resonator is that it allows higher frequency waves to bounce off a larger surface and thus cancel themselves out when you have two destructive waves colliding (aka /\/\ colliding with \/\/ wave). I also am assuming that the raspy sound from our exhaust comes from the higher frequency waves being able to penetrate the metal and thus resulting in a metalic vibrating sound.
As far as them dieing out b/c they get stuck in steel wool, i doubt that is entirely true seeing as that high freq sound waves have the ability to pass through matter, esp dense matter like metals. Having a bunch of material surrounding the resonator tube would possibly absorb the waves energy and that could possibly result in their deterioration.
Close maacus....the resonator actually cancels the higher amplitude waves. Higher amplitude=louder.
The reason it does that is because when they're flowing through the pipe they have nowhere to go, but when they hit the resonator, the holes in the pipe allow the wave to flow up and down more, and when they hit the steel wool once they get out of the holes in the pipe, they die out.
Keep in mind, these are our version of high flow "resonators"....they're honestly just straight through mufflers, resonators in their true form are much more restrictive, they involve sound waves cancelling each other.</TD></TR></TABLE>
Actualy ur wrong. Freq is the amt of space between the peaks of the sound waves and amplitude is how high/low the peaks are. Higher FREQ means more energy which equals louder. Low frequency (low energy) sound waves are the deeper tones you hear and are the ones created by the resonator. http://en.wikipedia.org/wiki/Frequency
My understanding of a resonator is that it allows higher frequency waves to bounce off a larger surface and thus cancel themselves out when you have two destructive waves colliding (aka /\/\ colliding with \/\/ wave). I also am assuming that the raspy sound from our exhaust comes from the higher frequency waves being able to penetrate the metal and thus resulting in a metalic vibrating sound.
As far as them dieing out b/c they get stuck in steel wool, i doubt that is entirely true seeing as that high freq sound waves have the ability to pass through matter, esp dense matter like metals. Having a bunch of material surrounding the resonator tube would possibly absorb the waves energy and that could possibly result in their deterioration.
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Firstly macus, they don't get "Stuck" in the steel wool, it simply slows down and reflects the waves in hopes of cancelling them out.
Higher Frequency does mean higher energy, but that does not mean louder. Frequency does determine pitch, for example, look at a drum set.
The bass drum is huge, and the material you hit is fairly loose. So when you hit it, as the vibrations travel from where you struck it to the edge of the drum and back, they can space themselves out more, which makes a longer wavelength. Talking in terms of wavelength is more appropriate here as frequency is relative to the speed of a wave, and since that isn't constant and can't realistically be determined, wavelength serves just as well. Wavelength is simply the space between the periods of the wave. So, back to the drums, the big loose drums make longer waves, which is a lower tone. Then take cymbals, they're smaller and made of metal, they make a much higher pitch due to the fact that metal cannot undulate as much as the plastic that they use on a bass drum, it simply vibrates in place, which creates a much shorter wavelength, and a higher pitch.
You can tune a true resonator to cancel out certain wavelengths of sound, by adjusting the length of various parts of the internals. Unfortunately these types of resonators are very restrictive.
A real resonator involves a tuned-length chamber with a tuned-size opening at one end that opens into a full chamber, this lets just a part of the approaching wave through into the second chamber, which then reflects back toward the opening, back into the main chamber, and cancels the incoming waves from the engine.
As I already said, the "resonators" we use on our cars are not really resonators in the true sense of the word, they're straight through mufflers.
Amplitude ..... Amplifier
Amplitude, as is suggested by its name, is what determines how loud a wave is to your ear. If you care to discuss this further, I'll show you how to calculate the exact scale of how your ears work and the decibel system and all, I'm not talking out of my *** here.
Anyways, the amplitude of a wave is directly related to its loudness, which is also related to the power of a wave, this is why turning your ipod way up kills the battery faster. If it was the way you describe it, that higher frequency waves are louder, or use more power, you would kill your batter just because of high pitched notes being played.
Since our ears hear on a logarithmic scale, the dB (decibel) scale, the amplitude of a wave is related to our hearing by a base 10 logarithm.
Anyways, enough of the lesson, now, you are right in saying that higher frequency waves are cancelled out by the "resonator" due to the destructive interference that it causes, though the overall effect of a muffler is to rob some amplitude from the waves.
Higher Frequency does mean higher energy, but that does not mean louder. Frequency does determine pitch, for example, look at a drum set.
The bass drum is huge, and the material you hit is fairly loose. So when you hit it, as the vibrations travel from where you struck it to the edge of the drum and back, they can space themselves out more, which makes a longer wavelength. Talking in terms of wavelength is more appropriate here as frequency is relative to the speed of a wave, and since that isn't constant and can't realistically be determined, wavelength serves just as well. Wavelength is simply the space between the periods of the wave. So, back to the drums, the big loose drums make longer waves, which is a lower tone. Then take cymbals, they're smaller and made of metal, they make a much higher pitch due to the fact that metal cannot undulate as much as the plastic that they use on a bass drum, it simply vibrates in place, which creates a much shorter wavelength, and a higher pitch.
You can tune a true resonator to cancel out certain wavelengths of sound, by adjusting the length of various parts of the internals. Unfortunately these types of resonators are very restrictive.
A real resonator involves a tuned-length chamber with a tuned-size opening at one end that opens into a full chamber, this lets just a part of the approaching wave through into the second chamber, which then reflects back toward the opening, back into the main chamber, and cancels the incoming waves from the engine.
As I already said, the "resonators" we use on our cars are not really resonators in the true sense of the word, they're straight through mufflers.
Amplitude ..... Amplifier
Amplitude, as is suggested by its name, is what determines how loud a wave is to your ear. If you care to discuss this further, I'll show you how to calculate the exact scale of how your ears work and the decibel system and all, I'm not talking out of my *** here.
Anyways, the amplitude of a wave is directly related to its loudness, which is also related to the power of a wave, this is why turning your ipod way up kills the battery faster. If it was the way you describe it, that higher frequency waves are louder, or use more power, you would kill your batter just because of high pitched notes being played.
Since our ears hear on a logarithmic scale, the dB (decibel) scale, the amplitude of a wave is related to our hearing by a base 10 logarithm.
Anyways, enough of the lesson, now, you are right in saying that higher frequency waves are cancelled out by the "resonator" due to the destructive interference that it causes, though the overall effect of a muffler is to rob some amplitude from the waves.
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Re: (mgags7)
Originally Posted by mgags7
Firstly macus, they don't get "Stuck" in the steel wool, it simply slows down and reflects the waves in hopes of cancelling them out.
Originally Posted by mgags7
Higher Frequency does mean higher energy, but that does not mean louder. Frequency does determine pitch, for example, look at a drum set.
The bass drum is huge, and the material you hit is fairly loose. So when you hit it, as the vibrations travel from where you struck it to the edge of the drum and back, they can space themselves out more, which makes a longer wavelength. Talking in terms of wavelength is more appropriate here as frequency is relative to the speed of a wave, and since that isn't constant and can't realistically be determined, wavelength serves just as well. Wavelength is simply the space between the periods of the wave. So, back to the drums, the big loose drums make longer waves, which is a lower tone. Then take cymbals, they're smaller and made of metal, they make a much higher pitch due to the fact that metal cannot undulate as much as the plastic that they use on a bass drum, it simply vibrates in place, which creates a much shorter wavelength, and a higher pitch.
The bass drum is huge, and the material you hit is fairly loose. So when you hit it, as the vibrations travel from where you struck it to the edge of the drum and back, they can space themselves out more, which makes a longer wavelength. Talking in terms of wavelength is more appropriate here as frequency is relative to the speed of a wave, and since that isn't constant and can't realistically be determined, wavelength serves just as well. Wavelength is simply the space between the periods of the wave. So, back to the drums, the big loose drums make longer waves, which is a lower tone. Then take cymbals, they're smaller and made of metal, they make a much higher pitch due to the fact that metal cannot undulate as much as the plastic that they use on a bass drum, it simply vibrates in place, which creates a much shorter wavelength, and a higher pitch.
Originally Posted by magags7
You can tune a true resonator to cancel out certain wavelengths of sound, by adjusting the length of various parts of the internals. Unfortunately these types of resonators are very restrictive.
A real resonator involves a tuned-length chamber with a tuned-size opening at one end that opens into a full chamber, this lets just a part of the approaching wave through into the second chamber, which then reflects back toward the opening, back into the main chamber, and cancels the incoming waves from the engine.
A real resonator involves a tuned-length chamber with a tuned-size opening at one end that opens into a full chamber, this lets just a part of the approaching wave through into the second chamber, which then reflects back toward the opening, back into the main chamber, and cancels the incoming waves from the engine.
Originally Posted by mgags7
As I already said, the "resonators" we use on our cars are not really resonators in the true sense of the word, they're straight through mufflers.
Originally Posted by mgags7
Anyways, the amplitude of a wave is directly related to its loudness, which is also related to the power of a wave, this is why turning your ipod way up kills the battery faster. If it was the way you describe it, that higher frequency waves are louder, or use more power, you would kill your batter just because of high pitched notes being played.
Since our ears hear on a logarithmic scale, the dB (decibel) scale, the amplitude of a wave is related to our hearing by a base 10 logarithm.
Originally Posted by mgags7
Anyways, enough of the lesson, now, you are right in saying that higher frequency waves are cancelled out by the "resonator" due to the destructive interference that it causes, though the overall effect of a muffler is to rob some amplitude from the waves.
I've typed so much im loosing sight of my point and argument
so im prob just gonna stop now....This tangent has gone far enough.PS I just stopped editing this in the middle of it b/c i got sick of typing, ill fix it later
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What energy do you mean marcus?
If you're talking about a sound wave, it has to move air molecules up and down, so a higher frequency wave would do that more often, which would be more work done per unit time.
I'm into waves and power and frequency way over my head right now in class, believe me, I'm not lying to you.
an expanded space, such as this style of straight through resonator, slows down the waves, which given a wavelength, would make the frequency lower.
If you're talking about a sound wave, it has to move air molecules up and down, so a higher frequency wave would do that more often, which would be more work done per unit time.
I'm into waves and power and frequency way over my head right now in class, believe me, I'm not lying to you.
an expanded space, such as this style of straight through resonator, slows down the waves, which given a wavelength, would make the frequency lower.
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Re: Help me decide: Straight pipe or high flow cat? (KB96VTEC)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by KB96VTEC »</TD></TR><TR><TD CLASS="quote">engine is 96 OBD2 H22a1. i already have AEM CAI and WS2 catback. Now i have ordered the megan header and plan to do the collector mod. I realize that to actually feel some gains something has to be done with the stock cat. I want to stay quiet as possible which is why i bought the WS2. Which would be best for my setup and would i need to convert to OBD1 to use a test pipe? im afraid a testpipe would ruin my quiet setup...</TD></TR></TABLE>
dude hate to thread jack but do u gotta pic of the ws2 exhaust on your car. and how do u like it. i got the apex n1 rite now but ive had it for about 5 years time for a new 1.
dude hate to thread jack but do u gotta pic of the ws2 exhaust on your car. and how do u like it. i got the apex n1 rite now but ive had it for about 5 years time for a new 1.
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Re: Help me decide: Straight pipe or high flow cat? (jdmlude5)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by jdmlude5 »</TD></TR><TR><TD CLASS="quote">
dude hate to thread jack but do u gotta pic of the ws2 exhaust on your car. and how do u like it. i got the apex n1 rite now but ive had it for about 5 years time for a new 1.</TD></TR></TABLE>
dude, theres a thing called a PM.. which you could message that user directly..
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mgags7 »</TD></TR><TR><TD CLASS="quote">What energy do you mean marcus?
If you're talking about a sound wave, </TD></TR></TABLE>
sound wave? what are you guys talking about?!.. i used to have a sound wave about 20 years back when i was a kid.. he used to transform into a tape recorder.. and had small transforming tapes with it.. he was damn cool. if i still had it.. it would probably be worth a lot now..
dude hate to thread jack but do u gotta pic of the ws2 exhaust on your car. and how do u like it. i got the apex n1 rite now but ive had it for about 5 years time for a new 1.</TD></TR></TABLE>
dude, theres a thing called a PM.. which you could message that user directly..
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mgags7 »</TD></TR><TR><TD CLASS="quote">What energy do you mean marcus?
If you're talking about a sound wave, </TD></TR></TABLE>
sound wave? what are you guys talking about?!.. i used to have a sound wave about 20 years back when i was a kid.. he used to transform into a tape recorder.. and had small transforming tapes with it.. he was damn cool. if i still had it.. it would probably be worth a lot now..
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Re: Help me decide: Straight pipe or high flow cat? (Mykizism)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Mykizism »</TD></TR><TR><TD CLASS="quote">
sound wave? what are you guys talking about?!.. i used to have a sound wave about 20 years back when i was a kid.. he used to transform into a tape recorder.. and had small transforming tapes with it.. he was damn cool. if i still had it.. it would probably be worth a lot now.. </TD></TR></TABLE>
^^^ bahahaaa
i would go with a high flow cat. my friend has a test pipe on his lude and im pretty sure thats why it smells funny every time he pulls up...
sound wave? what are you guys talking about?!.. i used to have a sound wave about 20 years back when i was a kid.. he used to transform into a tape recorder.. and had small transforming tapes with it.. he was damn cool. if i still had it.. it would probably be worth a lot now..
</TD></TR></TABLE>^^^ bahahaaa
i would go with a high flow cat. my friend has a test pipe on his lude and im pretty sure thats why it smells funny every time he pulls up...
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Re: Help me decide: Straight pipe or high flow cat? (Mykizism)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Mykizism »</TD></TR><TR><TD CLASS="quote">sound wave? what are you guys talking about?!.. i used to have a sound wave about 20 years back when i was a kid.. he used to transform into a tape recorder.. and had small transforming tapes with it.. he was damn cool. if i still had it.. it would probably be worth a lot now.. </TD></TR></TABLE>
lol
thats all I can say. bahahaha
</TD></TR></TABLE>lol
thats all I can say. bahahaha
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