Why do headers need to merge...?
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Joined: Jan 2003
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From: Mission Viejo, CA
Why do headers need to merge...?
Specifically, I'm talking about the s2000. why not just create a single pipe for each cylinder.... and have them split into two on each side.... no merging... just a straight pipe for each cylinder ALL the way through to the back?
Just curious... any engineers, mechanics, etc out there who can help with this question?
Best,
J
Just curious... any engineers, mechanics, etc out there who can help with this question?
Best,
J
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Joined: Jan 2007
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From: PA (near Pittsburgh)
Exhaust scavenging. To simplify it extremely, the different exhaust pulses help to "pull" out the exhaust gases from the head during the exhaust stroke... this in turn can evacuate the cylinder quicker and more completely. When you hear people say things like "too large of an exhaust killed my torque because there is not enough backpressure". that isnt the case. "Backpressure" is never a good thing, but keeping the exhaust gas velocity high is. Its a balancing act of making an exhaust as least restrictive as you can, while keeping velocity up. This is of course in N/A applications. For a turbo vehicle, the turbocharger itself is the largest restriction and from then on you pretty much want the largest exhaust you can get.
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From: SIN CITY - Las Vegas
Originally Posted by Rxmfn7,Jun 17 2008, 04:30 AM
Exhaust scavenging. To simplify it extremely, the different exhaust pulses help to "pull" out the exhaust gases from the head during the exhaust stroke... this in turn can evacuate the cylinder quicker and more completely. When you hear people say things like "too large of an exhaust killed my torque because there is not enough backpressure". that isnt the case. "Backpressure" is never a good thing, but keeping the exhaust gas velocity high is. Its a balancing act of making an exhaust as least restrictive as you can, while keeping velocity up. This is of course in N/A applications. For a turbo vehicle, the turbocharger itself is the largest restriction and from then on you pretty much want the largest exhaust you can get.
Joined: Jun 2006
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From: Raleigh, NC
Originally Posted by Rxmfn7,Jun 17 2008, 07:30 AM
Exhaust scavenging. To simplify it extremely, the different exhaust pulses help to "pull" out the exhaust gases from the head during the exhaust stroke... this in turn can evacuate the cylinder quicker and more completely. When you hear people say things like "too large of an exhaust killed my torque because there is not enough backpressure". that isnt the case. "Backpressure" is never a good thing, but keeping the exhaust gas velocity high is. Its a balancing act of making an exhaust as least restrictive as you can, while keeping velocity up. This is of course in N/A applications. For a turbo vehicle, the turbocharger itself is the largest restriction and from then on you pretty much want the largest exhaust you can get.
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From: Parrish, FL
+1. excellent description.
Glad someone got the "backpressure is never good" statement out right off the bat. It was inevitable that someone would've said "oh you need backpressure" somewhere in here, lol.
Glad someone got the "backpressure is never good" statement out right off the bat. It was inevitable that someone would've said "oh you need backpressure" somewhere in here, lol.
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