Is no muffler bad for your car?
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Is no muffler bad for your car?
Title reads the question.
Been hearing that mufflers provide down pressure or something of sorts to help the engine and with out the mufflers the head will dry out head not headers. Anyone know anything about this?
Been hearing that mufflers provide down pressure or something of sorts to help the engine and with out the mufflers the head will dry out head not headers. Anyone know anything about this?
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From: 1 hours drive north of Sydney Australia
2007 W204 220CDI Classic Sedan
I have run motor cycles without mufflers for years without any adverse effects.
Mufflers do add back pressure to to the combustion system .
I dare say the modern car engine is designed to give optimum performance with this back pressure.
Some have said that lessening the backpressure can burn exhaust valves.
I would say that this would not happen overnight!
Mufflers do add back pressure to to the combustion system .
I dare say the modern car engine is designed to give optimum performance with this back pressure.
Some have said that lessening the backpressure can burn exhaust valves.
I would say that this would not happen overnight!
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'08 C300 Lux Barolo Red Beige Leather P2 MM 18" wheels '84 944
And, it's backpressure.
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i don't see how exhaust valves will burn with less back pressure. If it's less back pressure, exhaust should be leaving at a faster velocity. maybe someone with more knowledge will clarify
Last edited by GHAZAN; Feb 25, 2011 at 01:00 AM.
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2007 W204 220CDI Classic Sedan
Exactly ,I would have thought that shutting hot gas off at a greater velocity will create more wear on the mating surfaces. .
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2008 C300 Sport 6 Speed Manual, 1953 Chevy Bel-Air, 2015 Audi allroad, 1963 Chevy Apache
With nothing else changing, reduced back pressure can cause an engine to run lean and hot (more air sucked in with the same amount of fuel injected) with the exhaust valve generally being the first part of the engine that may have issues.
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From: Dix Hills, New York
2012 C250 Coupe
The exhaust as it exits the piping is moving in the form of pulses or pressure waves with varying speeds and pressures. These pulses have mass, and want to continue moving at a high rate of speed. These pulses if they are moving fast enough, will create a low pressure region behind them and will help draw out more spent exhaust from the engine, and will create a region of lower pressure inside the exhaust manifold.
If the system is too short, the fast moving pulse will collapse as it exits the end of the pipe, and the low pressure wake will also collapse, reducing the scavenging effect, especially at low RPM. This will be felt as a decrease in performance right off the line.
As RPMS increase, the speed and frequency of these pressure waves increases, negating some of the performance losses and restoring the scavenging effect.
Exhaust scavenging is a function of velocity, not backpressure. Having lower backpressure is a good thing. If a modification decreases the velocity, then a low RPM power loss will be the result. In the case of cutting off the muffler and not at least replacing it with a straight pipe, this modification is reducing the opportunity for the exhaust to built up and keep the speed, and it instead slowing down the exhaust as it exits, creating more backpressure than the stock muffler.
An x-pipe creates a cross flow which allows the pressure waves to accelerate each other and create a positive induction.
If you replace your muffler with a piece of pipe, you will get the sound you are probably after without loosing the velocity that is essential to produce power.
If the system is too short, the fast moving pulse will collapse as it exits the end of the pipe, and the low pressure wake will also collapse, reducing the scavenging effect, especially at low RPM. This will be felt as a decrease in performance right off the line.
As RPMS increase, the speed and frequency of these pressure waves increases, negating some of the performance losses and restoring the scavenging effect.
Exhaust scavenging is a function of velocity, not backpressure. Having lower backpressure is a good thing. If a modification decreases the velocity, then a low RPM power loss will be the result. In the case of cutting off the muffler and not at least replacing it with a straight pipe, this modification is reducing the opportunity for the exhaust to built up and keep the speed, and it instead slowing down the exhaust as it exits, creating more backpressure than the stock muffler.
An x-pipe creates a cross flow which allows the pressure waves to accelerate each other and create a positive induction.
If you replace your muffler with a piece of pipe, you will get the sound you are probably after without loosing the velocity that is essential to produce power.
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Not this again
I have run motor cycles without mufflers for years without any adverse effects.
Mufflers do add back pressure to to the combustion system .
I dare say the modern car engine is designed to give optimum performance with this back pressure.
Some have said that lessening the backpressure can burn exhaust valves.
Mufflers do add back pressure to to the combustion system .
I dare say the modern car engine is designed to give optimum performance with this back pressure.
Some have said that lessening the backpressure can burn exhaust valves.
Now I ask you, does this make sense?
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Even carbureted engines operate this way although jets have to be changed to supply more fuel at high rpms.
The Porsches I owned with Weber triple throat carbs were modified with larger venturis which meant larger idle and main jets. But, enlarging the venturis meant a loss of low end torque. It's a tradeoff.
And, 4-valve heads without variable intake cam timing also costs low end performance.
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This theory is wrong. Intake air is measured by the mass airflow sensor which sends a signal to the engine management computer which, with other inputs, determines how much fuel to inject.
Even carbureted engines operate this way although jets have to be changed to supply more fuel at high rpms.
The Porsches I owned with Weber triple throat carbs were modified with larger venturis which meant larger idle and main jets. But, enlarging the venturis meant a loss of low end torque. It's a tradeoff.
And, 4-valve heads without variable intake cam timing also costs low end performance.
Even carbureted engines operate this way although jets have to be changed to supply more fuel at high rpms.
The Porsches I owned with Weber triple throat carbs were modified with larger venturis which meant larger idle and main jets. But, enlarging the venturis meant a loss of low end torque. It's a tradeoff.
And, 4-valve heads without variable intake cam timing also costs low end performance.
I opened up the exhaust and intake on my old school carburated bike and was running way to lean. If I wouldn't have rejetted, I would have fried the valves within 1000 miles.
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From: So-Cal
c350
I cut my mufflers off a while ago on the 350, no problem at all. And I drive it like I stole it every time. Then I installed headers and cat delete and put mufflers back on as the sounds was to much.
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great only around 2k its very annoying and around 1k-2k there is a noticeable vibration in the cabin 2.5k------- sound like xpipe muffler at 3k but a bit louder and for the whole duration instead for a little time. Outside the car I havent let anyone drive my car so idk based on friends, they say sounds great maybe at peak legal sound 95db in cali
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c350coupe, Gencoupe R-spec
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Is not bad for your engine, you may get some power increase and laud exhaust sound with vibration.
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From: LA
MB C-300 Sport 2009 Manual Black XPIPE+Exhaust
great only around 2k its very annoying and around 1k-2k there is a noticeable vibration in the cabin 2.5k------- sound like xpipe muffler at 3k but a bit louder and for the whole duration instead for a little time. Outside the car I havent let anyone drive my car so idk based on friends, they say sounds great maybe at peak legal sound 95db in cali
and i drive it a LOT!
