well stated
Difference between X and H Pipe
Thread Starter
Racer
Joined: May 2007
Posts: 281
Likes: 0
From: Monterrey, Mexico Nuevo Leon
Difference between X and H Pipe
Hi my friends...
Like a said before, I installed a B&B PRT on my 98 Coupe C5, today with just 7k Miles on it the car, but I dont like the sound, too much bubbling, and popping, , and because I almost dont use the car, last too much time to try new mods..
Right now, I´m thinking on replace the OEM H Pipe, for a X PIpe and take off the Cats just to see if the sound changes for something with better taste..
What do you say?, would change the type of sound??
Any one change H for a X?, which were the results?
Like a said before, I installed a B&B PRT on my 98 Coupe C5, today with just 7k Miles on it the car, but I dont like the sound, too much bubbling, and popping, , and because I almost dont use the car, last too much time to try new mods..
Right now, I´m thinking on replace the OEM H Pipe, for a X PIpe and take off the Cats just to see if the sound changes for something with better taste..
What do you say?, would change the type of sound??
Any one change H for a X?, which were the results?
Last edited by RogerArrambide; Dec 25, 2008 at 08:10 PM.
Melting Slicks
Joined: Apr 2007
Posts: 2,167
Likes: 55
From: Kempner TX
St. Jude Donor '08-'09
Basically the H pipe is a straight flow with no where for the gases to equalize. With the crossover the X offers, the gas can take the path of less resistance thus making the X pipe a better flowing exhaust.
Instructor
Joined: Dec 2008
Posts: 100
Likes: 0
From: Remember the average response time to a 911 call is over 6 minutes. The average response time of a .357 magnum is 1400 fps.
I thought the "H" pipe helped to equalize the difference in pressure between the two exhaust pipes, as it is a direct connection. And the "X" pipe added improved scavenging for increased flow.
Pro
Joined: Mar 2007
Posts: 651
Likes: 0
From: Ashland Kentucky
Safety Car
Joined: Sep 2007
Posts: 4,005
Likes: 489
From: South Florida
It will absolutely change the sound of the exhaust, but in a good way. It will sound much deeper at idle and WOT, will be louder, and will burble less. Say goodbye to the motorboat sound.
Dave
Dave
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Safety Car
Joined: Apr 2003
Posts: 3,732
Likes: 21
From: Napa Ca
I was going to say don't remove the cats since that would be illegal in California...then I looked in your profile and its Monterrey, Mexico. I have PRTs and they don't bother me at all with the stock cats and H-pipe.
Melting Slicks
Joined: Jun 2007
Posts: 2,263
Likes: 0
From: Paducah Kentucky
Thread Starter
Racer
Joined: May 2007
Posts: 281
Likes: 0
From: Monterrey, Mexico Nuevo Leon
My friends with Vettes and FBodies didnt liked too, I was thinking to return stock just for the sound, but then I thought that with X Pipe, because the flow changes, may be a better sound.
When I thought on replace stock catback, it was just to put some personality to the car, but didnt liked to be like my LS1 SS with TrueDual, I mean I like too much that sound for the Camaro but for my Vette, just wanted a little noise, then, decide for this PRT, but like I said, didnt liked JUST for the "motorboat sound" but the noise from 2000rpms to WOT are ok, the resonance is good enough, so, I just need to stop that burble...
Any one has an X Pipe?
Other question: Can someone define "SCAVENGE"??
Instructor
Joined: Dec 2008
Posts: 100
Likes: 0
From: Remember the average response time to a 911 call is over 6 minutes. The average response time of a .357 magnum is 1400 fps.
From Wikipedia:
Exhaust Scavenging
When an engine starts its exhaust stroke, the piston moves up the cylinder bore, decreasing the total chamber volume. With the exhaust valve open, the high pressure exhaust gas escapes into the exhaust manifold or header, creating an exhaust pulse comprising three main parts: The high-pressure head is created by the large pressure difference between the exhaust in the combustion chamber and the atmospheric pressure outside of the exhaust system. As the exhaust gases equalize between the combustion chamber and the atmosphere, the difference in pressure decreases and the exhaust velocity decreases. This forms the medium-pressure body component of the exhaust pulse. The remaining exhaust gas forms the low-pressure tail component. This tail component may initially match ambient atmospheric pressure, but the momentum of the high- and medium- pressure components reduces the pressure in the combustion chamber to a lower-than-atmospheric level. This relatively low pressure helps to extract all the spent fuel from the cylinder and induct the intake charge during the overlap period when both intake and exhaust valves are partially open. The effect is known as scavenging. Length, cross-sectional area, and shaping of the exhaust ports and pipeworks influences the degree of scavenging effect, and the engine speed range over which scavenging occurs.
The magnitude of the exhaust scavenging effect is a direct function of the velocity of the high and medium pressure components of the exhaust pulse. Performance headers work to increase the exhaust velocity as much as possible. One technique is tuned-length primary tubes. This technique attempts to time the occurrence of each exhaust pulse, to occur one after the other in succession while still in the exhaust system. The lower pressure tail of an exhaust pulse then serves to create a greater pressure difference between the high pressure head of the next exhaust pulse, thus increasing the velocity of that exhaust pulse. In V6 and V8 engines where there is more than one exhaust bank, Y-pipes and X-pipes work on the same principle of using the low pressure component of an exhaust pulse to increase the velocity of the next exhaust pulse.
Great care must be used when selecting the length and diameter of the primary tubes. Tubes that are too large will cause the exhaust gas to expand and slow down, decreasing the scavenging effect. Tubes that are too small will create backpressure against which the engine must work to expel the exhaust gas from the chamber, reducing power and leaving exhaust in the chamber to dilute the incoming intake charge. Since engines produce more exhaust gas at higher speeds, the header(s) are tuned to a particular engine speed range according to the intended application. Typically, large primary tubes offer the best gains in power and torque at higher engine speeds, while smaller tubes offer the best gains at lower speeds.
Many headers are also resonance tuned, to utilize the low-pressure reflected wave rarefaction pulse which can help scavenging the combustion chamber during valve overlap. This pulse is created in all exhaust systems each time a change in density occurs, such as when exhaust merges into the collector. For clarification, the rarefaction pulse is the technical term for the same process that was described above in the "head, body, tail" description. By tuning the length of the primary tubes, usually by means of resonance tuning, the rarefaction pulse can be timed to coincide with the exact moment valve overlap occurs.
Some modern exhaust headers are available with a ceramic coating. This coating serves to prohibit rust and to reduce the amount of heat radiated into the engine bay. The heat reduction will help prevent intake manifold heat soak, which will decrease the temperature of the air entering the engine.
HTH
Exhaust Scavenging
When an engine starts its exhaust stroke, the piston moves up the cylinder bore, decreasing the total chamber volume. With the exhaust valve open, the high pressure exhaust gas escapes into the exhaust manifold or header, creating an exhaust pulse comprising three main parts: The high-pressure head is created by the large pressure difference between the exhaust in the combustion chamber and the atmospheric pressure outside of the exhaust system. As the exhaust gases equalize between the combustion chamber and the atmosphere, the difference in pressure decreases and the exhaust velocity decreases. This forms the medium-pressure body component of the exhaust pulse. The remaining exhaust gas forms the low-pressure tail component. This tail component may initially match ambient atmospheric pressure, but the momentum of the high- and medium- pressure components reduces the pressure in the combustion chamber to a lower-than-atmospheric level. This relatively low pressure helps to extract all the spent fuel from the cylinder and induct the intake charge during the overlap period when both intake and exhaust valves are partially open. The effect is known as scavenging. Length, cross-sectional area, and shaping of the exhaust ports and pipeworks influences the degree of scavenging effect, and the engine speed range over which scavenging occurs.
The magnitude of the exhaust scavenging effect is a direct function of the velocity of the high and medium pressure components of the exhaust pulse. Performance headers work to increase the exhaust velocity as much as possible. One technique is tuned-length primary tubes. This technique attempts to time the occurrence of each exhaust pulse, to occur one after the other in succession while still in the exhaust system. The lower pressure tail of an exhaust pulse then serves to create a greater pressure difference between the high pressure head of the next exhaust pulse, thus increasing the velocity of that exhaust pulse. In V6 and V8 engines where there is more than one exhaust bank, Y-pipes and X-pipes work on the same principle of using the low pressure component of an exhaust pulse to increase the velocity of the next exhaust pulse.
Great care must be used when selecting the length and diameter of the primary tubes. Tubes that are too large will cause the exhaust gas to expand and slow down, decreasing the scavenging effect. Tubes that are too small will create backpressure against which the engine must work to expel the exhaust gas from the chamber, reducing power and leaving exhaust in the chamber to dilute the incoming intake charge. Since engines produce more exhaust gas at higher speeds, the header(s) are tuned to a particular engine speed range according to the intended application. Typically, large primary tubes offer the best gains in power and torque at higher engine speeds, while smaller tubes offer the best gains at lower speeds.
Many headers are also resonance tuned, to utilize the low-pressure reflected wave rarefaction pulse which can help scavenging the combustion chamber during valve overlap. This pulse is created in all exhaust systems each time a change in density occurs, such as when exhaust merges into the collector. For clarification, the rarefaction pulse is the technical term for the same process that was described above in the "head, body, tail" description. By tuning the length of the primary tubes, usually by means of resonance tuning, the rarefaction pulse can be timed to coincide with the exact moment valve overlap occurs.
Some modern exhaust headers are available with a ceramic coating. This coating serves to prohibit rust and to reduce the amount of heat radiated into the engine bay. The heat reduction will help prevent intake manifold heat soak, which will decrease the temperature of the air entering the engine.
HTH
Thread Starter
Racer
Joined: May 2007
Posts: 281
Likes: 0
From: Monterrey, Mexico Nuevo Leon
From Wikipedia:
Exhaust Scavenging
When an engine starts its exhaust stroke, the piston moves up the cylinder bore, decreasing the total chamber volume. With the exhaust valve open, the high pressure exhaust gas escapes into the exhaust manifold or header, creating an exhaust pulse comprising three main parts: The high-pressure head is created by the large pressure difference between the exhaust in the combustion chamber and the atmospheric pressure outside of the exhaust system. As the exhaust gases equalize between the combustion chamber and the atmosphere, the difference in pressure decreases and the exhaust velocity decreases. This forms the medium-pressure body component of the exhaust pulse. The remaining exhaust gas forms the low-pressure tail component. This tail component may initially match ambient atmospheric pressure, but the momentum of the high- and medium- pressure components reduces the pressure in the combustion chamber to a lower-than-atmospheric level. This relatively low pressure helps to extract all the spent fuel from the cylinder and induct the intake charge during the overlap period when both intake and exhaust valves are partially open. The effect is known as scavenging. Length, cross-sectional area, and shaping of the exhaust ports and pipeworks influences the degree of scavenging effect, and the engine speed range over which scavenging occurs.
The magnitude of the exhaust scavenging effect is a direct function of the velocity of the high and medium pressure components of the exhaust pulse. Performance headers work to increase the exhaust velocity as much as possible. One technique is tuned-length primary tubes. This technique attempts to time the occurrence of each exhaust pulse, to occur one after the other in succession while still in the exhaust system. The lower pressure tail of an exhaust pulse then serves to create a greater pressure difference between the high pressure head of the next exhaust pulse, thus increasing the velocity of that exhaust pulse. In V6 and V8 engines where there is more than one exhaust bank, Y-pipes and X-pipes work on the same principle of using the low pressure component of an exhaust pulse to increase the velocity of the next exhaust pulse.
Great care must be used when selecting the length and diameter of the primary tubes. Tubes that are too large will cause the exhaust gas to expand and slow down, decreasing the scavenging effect. Tubes that are too small will create backpressure against which the engine must work to expel the exhaust gas from the chamber, reducing power and leaving exhaust in the chamber to dilute the incoming intake charge. Since engines produce more exhaust gas at higher speeds, the header(s) are tuned to a particular engine speed range according to the intended application. Typically, large primary tubes offer the best gains in power and torque at higher engine speeds, while smaller tubes offer the best gains at lower speeds.
Many headers are also resonance tuned, to utilize the low-pressure reflected wave rarefaction pulse which can help scavenging the combustion chamber during valve overlap. This pulse is created in all exhaust systems each time a change in density occurs, such as when exhaust merges into the collector. For clarification, the rarefaction pulse is the technical term for the same process that was described above in the "head, body, tail" description. By tuning the length of the primary tubes, usually by means of resonance tuning, the rarefaction pulse can be timed to coincide with the exact moment valve overlap occurs.
Some modern exhaust headers are available with a ceramic coating. This coating serves to prohibit rust and to reduce the amount of heat radiated into the engine bay. The heat reduction will help prevent intake manifold heat soak, which will decrease the temperature of the air entering the engine.
HTH
Exhaust Scavenging
When an engine starts its exhaust stroke, the piston moves up the cylinder bore, decreasing the total chamber volume. With the exhaust valve open, the high pressure exhaust gas escapes into the exhaust manifold or header, creating an exhaust pulse comprising three main parts: The high-pressure head is created by the large pressure difference between the exhaust in the combustion chamber and the atmospheric pressure outside of the exhaust system. As the exhaust gases equalize between the combustion chamber and the atmosphere, the difference in pressure decreases and the exhaust velocity decreases. This forms the medium-pressure body component of the exhaust pulse. The remaining exhaust gas forms the low-pressure tail component. This tail component may initially match ambient atmospheric pressure, but the momentum of the high- and medium- pressure components reduces the pressure in the combustion chamber to a lower-than-atmospheric level. This relatively low pressure helps to extract all the spent fuel from the cylinder and induct the intake charge during the overlap period when both intake and exhaust valves are partially open. The effect is known as scavenging. Length, cross-sectional area, and shaping of the exhaust ports and pipeworks influences the degree of scavenging effect, and the engine speed range over which scavenging occurs.
The magnitude of the exhaust scavenging effect is a direct function of the velocity of the high and medium pressure components of the exhaust pulse. Performance headers work to increase the exhaust velocity as much as possible. One technique is tuned-length primary tubes. This technique attempts to time the occurrence of each exhaust pulse, to occur one after the other in succession while still in the exhaust system. The lower pressure tail of an exhaust pulse then serves to create a greater pressure difference between the high pressure head of the next exhaust pulse, thus increasing the velocity of that exhaust pulse. In V6 and V8 engines where there is more than one exhaust bank, Y-pipes and X-pipes work on the same principle of using the low pressure component of an exhaust pulse to increase the velocity of the next exhaust pulse.
Great care must be used when selecting the length and diameter of the primary tubes. Tubes that are too large will cause the exhaust gas to expand and slow down, decreasing the scavenging effect. Tubes that are too small will create backpressure against which the engine must work to expel the exhaust gas from the chamber, reducing power and leaving exhaust in the chamber to dilute the incoming intake charge. Since engines produce more exhaust gas at higher speeds, the header(s) are tuned to a particular engine speed range according to the intended application. Typically, large primary tubes offer the best gains in power and torque at higher engine speeds, while smaller tubes offer the best gains at lower speeds.
Many headers are also resonance tuned, to utilize the low-pressure reflected wave rarefaction pulse which can help scavenging the combustion chamber during valve overlap. This pulse is created in all exhaust systems each time a change in density occurs, such as when exhaust merges into the collector. For clarification, the rarefaction pulse is the technical term for the same process that was described above in the "head, body, tail" description. By tuning the length of the primary tubes, usually by means of resonance tuning, the rarefaction pulse can be timed to coincide with the exact moment valve overlap occurs.
Some modern exhaust headers are available with a ceramic coating. This coating serves to prohibit rust and to reduce the amount of heat radiated into the engine bay. The heat reduction will help prevent intake manifold heat soak, which will decrease the temperature of the air entering the engine.
HTH
I understand almost everything, I mean almost because my spoken language is Spanish and just a little english, so, I will try to fin more information in spanish, any one knows the literally traduction of scavenging?
Team Owner
Joined: Aug 2003
Posts: 24,987
Likes: 26
From: Kerrville, Texas USA Hook 'em Horns!
CentralTX Events Coordinator
St. Jude Donor '03-'04-'05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15-'16-'17
Now that the theory has been explained, here is a picture. X pipe on the left, stock H pipe on the right.
Safety Car
Joined: Oct 2000
Posts: 4,949
Likes: 10
From: Monticello MN
Hi my friends...
Like a said before, I installed a B&B PRT on my 98 Coupe C5, today with just 7k Miles on it the car, but I dont like the sound, too much bubbling, and popping, , and because I almost dont use the car, last too much time to try new mods..
Right now, I´m thinking on replace the OEM H Pipe, for a X PIpe and take off the Cats just to see if the sound changes for something with better taste..
What do you say?, would change the type of sound??
Any one change H for a X?, which were the results?
Like a said before, I installed a B&B PRT on my 98 Coupe C5, today with just 7k Miles on it the car, but I dont like the sound, too much bubbling, and popping, , and because I almost dont use the car, last too much time to try new mods..
Right now, I´m thinking on replace the OEM H Pipe, for a X PIpe and take off the Cats just to see if the sound changes for something with better taste..
What do you say?, would change the type of sound??
Any one change H for a X?, which were the results?
A benefit of an X-pipe, over an H-pipe, in addition to a greater scavenging effect, is a "smoothing" of the exhaust tone and a reduction in the "popping" sound, that seems to come with many aftermarket exhausts, and some people don't like. With just an H-pipe, each exhaust pulse travels down it's exhaust pipe until it comes to the H-pipe. At that point, some of the pulse will cross over into the other exhaust pipe because of differential pressure (lower pressure on the non-firing side), creating the aforementioned scavenging effect. As some of the pulse is crossing over, and, therefore, taking a longer path out to the tailpipe, the result is basically non-synchronous pulses out the tail pipes, and one larger than the other.
With an X-pipe, both exhaust paths join. So now, when an exhaust pulse exits the X-pipe, a relatively equal amount of pulse is traveling down each exhaust pipe. The result is relatively equally sized, synchronous, exhaust pulses exiting the tailpipes, thereby "smoothing" the sound. This is in addition to a greater scavenging effect due to a larger pulse exiting the non-firing side tailpipe.
Ed
Burning Brakes
Joined: Dec 2006
Posts: 1,092
Likes: 0
From: Deerfield VA
St. Jude Donor '07
I have the Magnaflow TRUE-X setup on my Corvette, it sounds awesome! I have headers, SLP X pipe and flowmaster '40's on my MUSTANG GT, and it sounds ABSOLUTELY EVIL, I LOVE IT. I'm sold on X pipes!
John
John
Drifting
Joined: Apr 2007
Posts: 1,760
Likes: 4
From: Broward County Florida
Hi my friends...
Like a said before, I installed a B&B PRT on my 98 Coupe C5, today with just 7k Miles on it the car, but I dont like the sound, too much bubbling, and popping, , and because I almost dont use the car, last too much time to try new mods..
Right now, I´m thinking on replace the OEM H Pipe, for a X PIpe and take off the Cats just to see if the sound changes for something with better taste..
What do you say?, would change the type of sound??
Any one change H for a X?, which were the results?
Like a said before, I installed a B&B PRT on my 98 Coupe C5, today with just 7k Miles on it the car, but I dont like the sound, too much bubbling, and popping, , and because I almost dont use the car, last too much time to try new mods..
Right now, I´m thinking on replace the OEM H Pipe, for a X PIpe and take off the Cats just to see if the sound changes for something with better taste..
What do you say?, would change the type of sound??
Any one change H for a X?, which were the results?
Instructor
Joined: Dec 2008
Posts: 100
Likes: 0
From: Remember the average response time to a 911 call is over 6 minutes. The average response time of a .357 magnum is 1400 fps.
En español
De Wikipedia:
Barrido del extractor Cuando un motor comienza su movimiento de extractor, el pistón levanta el cilindro, disminuyendo el volumen de compartimiento total. Con la válvula de escape abierta, el gas de escape de alta presión se escapa en el múltiple o el jefe de extractor, creando un pulso del extractor que abarca tres porciones principales: La cabeza de alta presión es creada por la diferencia grande de la presión entre el extractor en la cámara de combustión y la presión atmosférica fuera del dispositivo de escape. Mientras que los gas de escape igualan entre la cámara de combustión y la atmósfera, la diferencia en la presión disminuye y la velocidad del extractor disminuye. Esto forma el componente del cuerpo de la medio-presión del pulso del extractor. El gas de escape restante forma el componente de baja presión de la cola. Este componente de la cola puede emparejar inicialmente la presión atmosférica ambiente, pero el ímpetu de los componentes high- y medios de la presión reduce la presión en la cámara de combustión a un nivel bajo-que-atmosférico. Esta presión relativamente baja ayuda a extraer todo el combustible gastado del cilindro y a instalar la carga del producto durante el período del traslapo en que las válvulas de escape del producto y están parcialmente abiertas. El efecto se conoce como barrido. La longitud, la superficie transversal, y el formar de los puertos de extractor y de los pipeworks influencia el grado de efecto de barrido, y la gama de la velocidad del motor sobre la cual el barrido ocurre.
La magnitud del efecto de barrido del extractor es una función directa de la velocidad de los componentes altos y medios de la presión del pulso del extractor. Los jefes del funcionamiento trabajan para aumentar la velocidad del extractor tanto cuanto sea posible. Una técnica es tubos primarios de la templar-longitud. Esta técnica intenta medir el tiempo de la ocurrencia de cada pulso del extractor, para ocurrir uno después del otro en la sucesión mientras que aún en el dispositivo de escape. La cola de una presión más baja de un pulso del extractor entonces sirve crear una mayor diferencia de la presión entre el jefe de alta presión del pulso siguiente del extractor, así aumentando la velocidad de ese pulso del extractor. En motores de V6 y de V8 donde hay más de un banco del extractor, las Y-pipas y las X-pipas funcionan en el mismo principio de usar el componente de la presión baja de un pulso del extractor para aumentar la velocidad del pulso siguiente del extractor.
El gran cuidado debe ser utilizado al seleccionar la longitud y el diámetro de los tubos primarios. Los tubos que son demasiado grandes harán el gas de escape ampliarse y retrasar, disminuyendo el efecto de barrido. Los tubos que son demasiado pequeños crearán la contrapresión contra la cual el motor debe trabajar para expeler el gas de escape del compartimiento, energía de reducción y dejar el extractor en el compartimiento para diluir la carga entrante del producto. Desde los motores produzca más gas de escape a velocidades más altas, los jefes se templan a una gama particular de la velocidad del motor según el uso previsto.
Típicamente, los tubos primarios grandes ofrecen los mejores aumentos de la energía y del esfuerzo de torsión a velocidades del motor más altas, mientras que tubos más pequeños ofrecen los mejores aumentos a velocidades más bajas.
Muchos jefes son también resonancia templados, para utilizar el pulso de baja presión de la rarefacción de la onda reflejada que puede ayudar a limpiar la cámara de combustión durante traslapo de la válvula. Este pulso se crea en todos los dispositivos de escape cada vez que ocurre un cambio en densidad, por ejemplo cuando el extractor se combina en el colector. Para la clarificación, el pulso de la rarefacción es el término técnico para el mismo proceso que fue descrito arriba en el " cabeza, cuerpo, tail" descripción. Templando la longitud de los tubos primarios, generalmente por medio de la resonancia que templa, el pulso de la rarefacción se puede medir el tiempo para coincidir con el traslapo exacto de la válvula del momento ocurre.
Algunos jefes modernos del extractor están disponibles con una capa de cerámica. Esta capa sirve prohibir moho y reducir la cantidad de calor irradiada en la bahía de motor. La reducción del calor ayudará a prevenir el calor del múltiple de producto empapa, que disminuirá la temperatura del aire que entra en el motor.
Did this work? Web Site Translator
De Wikipedia:
Barrido del extractor Cuando un motor comienza su movimiento de extractor, el pistón levanta el cilindro, disminuyendo el volumen de compartimiento total. Con la válvula de escape abierta, el gas de escape de alta presión se escapa en el múltiple o el jefe de extractor, creando un pulso del extractor que abarca tres porciones principales: La cabeza de alta presión es creada por la diferencia grande de la presión entre el extractor en la cámara de combustión y la presión atmosférica fuera del dispositivo de escape. Mientras que los gas de escape igualan entre la cámara de combustión y la atmósfera, la diferencia en la presión disminuye y la velocidad del extractor disminuye. Esto forma el componente del cuerpo de la medio-presión del pulso del extractor. El gas de escape restante forma el componente de baja presión de la cola. Este componente de la cola puede emparejar inicialmente la presión atmosférica ambiente, pero el ímpetu de los componentes high- y medios de la presión reduce la presión en la cámara de combustión a un nivel bajo-que-atmosférico. Esta presión relativamente baja ayuda a extraer todo el combustible gastado del cilindro y a instalar la carga del producto durante el período del traslapo en que las válvulas de escape del producto y están parcialmente abiertas. El efecto se conoce como barrido. La longitud, la superficie transversal, y el formar de los puertos de extractor y de los pipeworks influencia el grado de efecto de barrido, y la gama de la velocidad del motor sobre la cual el barrido ocurre.
La magnitud del efecto de barrido del extractor es una función directa de la velocidad de los componentes altos y medios de la presión del pulso del extractor. Los jefes del funcionamiento trabajan para aumentar la velocidad del extractor tanto cuanto sea posible. Una técnica es tubos primarios de la templar-longitud. Esta técnica intenta medir el tiempo de la ocurrencia de cada pulso del extractor, para ocurrir uno después del otro en la sucesión mientras que aún en el dispositivo de escape. La cola de una presión más baja de un pulso del extractor entonces sirve crear una mayor diferencia de la presión entre el jefe de alta presión del pulso siguiente del extractor, así aumentando la velocidad de ese pulso del extractor. En motores de V6 y de V8 donde hay más de un banco del extractor, las Y-pipas y las X-pipas funcionan en el mismo principio de usar el componente de la presión baja de un pulso del extractor para aumentar la velocidad del pulso siguiente del extractor.
El gran cuidado debe ser utilizado al seleccionar la longitud y el diámetro de los tubos primarios. Los tubos que son demasiado grandes harán el gas de escape ampliarse y retrasar, disminuyendo el efecto de barrido. Los tubos que son demasiado pequeños crearán la contrapresión contra la cual el motor debe trabajar para expeler el gas de escape del compartimiento, energía de reducción y dejar el extractor en el compartimiento para diluir la carga entrante del producto. Desde los motores produzca más gas de escape a velocidades más altas, los jefes se templan a una gama particular de la velocidad del motor según el uso previsto.
Típicamente, los tubos primarios grandes ofrecen los mejores aumentos de la energía y del esfuerzo de torsión a velocidades del motor más altas, mientras que tubos más pequeños ofrecen los mejores aumentos a velocidades más bajas.
Muchos jefes son también resonancia templados, para utilizar el pulso de baja presión de la rarefacción de la onda reflejada que puede ayudar a limpiar la cámara de combustión durante traslapo de la válvula. Este pulso se crea en todos los dispositivos de escape cada vez que ocurre un cambio en densidad, por ejemplo cuando el extractor se combina en el colector. Para la clarificación, el pulso de la rarefacción es el término técnico para el mismo proceso que fue descrito arriba en el " cabeza, cuerpo, tail" descripción. Templando la longitud de los tubos primarios, generalmente por medio de la resonancia que templa, el pulso de la rarefacción se puede medir el tiempo para coincidir con el traslapo exacto de la válvula del momento ocurre.
Algunos jefes modernos del extractor están disponibles con una capa de cerámica. Esta capa sirve prohibir moho y reducir la cantidad de calor irradiada en la bahía de motor. La reducción del calor ayudará a prevenir el calor del múltiple de producto empapa, que disminuirá la temperatura del aire que entra en el motor.
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