theory question- improving exhaust scavenging
02-20-2005, 09:40 PM
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theory question- improving exhaust scavenging
okay i got to thinking, and came up with an idea.
if u created a header with a indentation inside it that spins the exhaust air, could this be used to exude a greater vacuum behind the exhaust pulse, creating a larger scavenging effect on the air (sucking exhaust out of combustion chamber)? or would it create too much backpressure from packing the exhaust gasses denser?
on another note, you could use some form of vacuum directly adjacent to the exiting exhaust (right in front of where the exhaust exits the head) to create the same effect. perhaps some kind of system that gets vacuum from the intake charge, with some kind of 1 way valve or catch-can style filter to reroute the exhaust gasses away from returning into the intake.
these ideas are all just hypothetical and not all though out, somebody tell me why this wouldn't work or how it would be counter-productive.
if u created a header with a indentation inside it that spins the exhaust air, could this be used to exude a greater vacuum behind the exhaust pulse, creating a larger scavenging effect on the air (sucking exhaust out of combustion chamber)? or would it create too much backpressure from packing the exhaust gasses denser?
on another note, you could use some form of vacuum directly adjacent to the exiting exhaust (right in front of where the exhaust exits the head) to create the same effect. perhaps some kind of system that gets vacuum from the intake charge, with some kind of 1 way valve or catch-can style filter to reroute the exhaust gasses away from returning into the intake.
these ideas are all just hypothetical and not all though out, somebody tell me why this wouldn't work or how it would be counter-productive.
02-21-2005, 05:30 AM
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Re: theory question- improving exhaust scavenging (wdwalker)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by wdwalker »</TD></TR><TR><TD CLASS="quote">okay i got to thinking, and came up with an idea.
if u created a header with a indentation inside it that spins the exhaust air, could this be used to exude a greater vacuum behind the exhaust pulse, creating a larger scavenging effect on the air (sucking exhaust out of combustion chamber)? or would it create too much backpressure from packing the exhaust gasses denser?
on another note, you could use some form of vacuum directly adjacent to the exiting exhaust (right in front of where the exhaust exits the head) to create the same effect. perhaps some kind of system that gets vacuum from the intake charge, with some kind of 1 way valve or catch-can style filter to reroute the exhaust gasses away from returning into the intake.
these ideas are all just hypothetical and not all though out, somebody tell me why this wouldn't work or how it would be counter-productive. </TD></TR></TABLE>
anything that is placed inside the header will create backpressure wheter it spins or not. with the vacuum setup that might work but probably not a reliable setup on a daily driver, not many things can stand up to exhaust heat.
if u created a header with a indentation inside it that spins the exhaust air, could this be used to exude a greater vacuum behind the exhaust pulse, creating a larger scavenging effect on the air (sucking exhaust out of combustion chamber)? or would it create too much backpressure from packing the exhaust gasses denser?
on another note, you could use some form of vacuum directly adjacent to the exiting exhaust (right in front of where the exhaust exits the head) to create the same effect. perhaps some kind of system that gets vacuum from the intake charge, with some kind of 1 way valve or catch-can style filter to reroute the exhaust gasses away from returning into the intake.
these ideas are all just hypothetical and not all though out, somebody tell me why this wouldn't work or how it would be counter-productive.
</TD></TR></TABLE>anything that is placed inside the header will create backpressure wheter it spins or not. with the vacuum setup that might work but probably not a reliable setup on a daily driver, not many things can stand up to exhaust heat.
02-21-2005, 06:36 AM
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Re: theory question- improving exhaust scavenging (Boostage)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Boostage »</TD></TR><TR><TD CLASS="quote">not many things can stand up to exhaust heat.</TD></TR></TABLE>
how about those metal brake lines? seems like they would work pretty well. only thing i can't figure out is how to get a vacuum from the intake charge without recirculating exhaust gasses into the engine. how effectively could the gasses be filtered out, i'm pretty sure there would be almost zero usable o2 in the combusted gasses. it'd always end up being almost like a pcv system, recirculating the engine's byproducts for emissions purposes. how could i create a 1-way valve preventing recirculation of these gasses? maybe some kind of pressure-based actuator that diverts the air through another passage back into the exhaust at the downpipe, or a solenoid that opens to divert the air?
how about those metal brake lines? seems like they would work pretty well. only thing i can't figure out is how to get a vacuum from the intake charge without recirculating exhaust gasses into the engine. how effectively could the gasses be filtered out, i'm pretty sure there would be almost zero usable o2 in the combusted gasses. it'd always end up being almost like a pcv system, recirculating the engine's byproducts for emissions purposes. how could i create a 1-way valve preventing recirculation of these gasses? maybe some kind of pressure-based actuator that diverts the air through another passage back into the exhaust at the downpipe, or a solenoid that opens to divert the air?
02-21-2005, 06:43 AM
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Re: theory question- improving exhaust scavenging (wdwalker)
the spiral idea would slow down exhaust velocity.
As far as creating vacuum with the intake; exhaust flow has a way higher velocity than the intake, and its also too fast for any kind of pump.
To keep exhaust vel. up you could use turns after the exit from the head; play with tampered pipes and use megaphones
As far as creating vacuum with the intake; exhaust flow has a way higher velocity than the intake, and its also too fast for any kind of pump.
To keep exhaust vel. up you could use turns after the exit from the head; play with tampered pipes and use megaphones
02-21-2005, 01:46 PM
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Re: theory question- improving exhaust scavenging (wdwalker)
