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I have seen a few different aftermarket exhausts on our threads. Just wondering if anyone has compared these to just a straight pipe and can comment on the differences in sound. Also, does anyone know of a tailpipe insert that can quiet an aftermarket exhaust back down to stock for when We need to "behave"? Any downside to the car doing this?

Thx
 

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Check out the other threads on the Centerline Corsa exhaust to get real world feed back. Don't think straight pipes would be a much covered topic unless you were on a racing thread.
 

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I have seen a few different aftermarket exhausts on our threads. Just wondering if anyone has compared these to just a straight pipe and can comment on the differences in sound. Also, does anyone know of a tailpipe insert that can quiet an aftermarket exhaust back down to stock for when We need to "behave"? Any downside to the car doing this?

Thx
@pradeept08 is also a member on here.. see his video below.

 

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I forgot about Pradeeps car. Imho, the Corsa exhaust sounds much better, a more deeper throatier exhaust.
 

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I have seen a few different aftermarket exhausts on our threads. Just wondering if anyone has compared these to just a straight pipe and can comment on the differences in sound.
In out testing with the Corsa system we did try a straight pipe system.

What we found was that the overall volume wasn't much louder with a straight pipe, but adding a center resonator definitely improved the sound quality and tone of the system.
 

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You want inserts to deaden the sound? You should hear one first then decide if it's for you. Are you a Lusso or Ti Sport guy? It's really a great sounding system. i can't wait for the V2 cold air set up.
 

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Inserts work on motorcycle exhausts because they are inserted basically directly into the exaust system, providing return path of the exhaust gases back into sound deafening structure or into packing....on cars inserts would really just reduce the diameter of exit pipe, probably providing zero attenuation beside chocking the engine...pretty sure that is why I have never seen a car exaust with inserts but many motorcycle exhausts have that option
 

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2018 Q4 with Fiamenghi Ti exhaust, Race Mod, and Tecnico wheels.
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Inserts work on motorcycle exhausts because they are inserted basically directly into the exaust system, providing return path of the
exhaust gases back into sound deafening structure or into packing....on cars inserts would really just reduce the diameter of exit pipe, probably providing zero attenuation beside chocking the engine...pretty sure that is why I have never seen a car exaust with inserts but many motorcycle exhausts have that option
Having spent some time studying rigid acoustic filters, the general idea is to use a series of energy storage devices: accumulators (cavities) and kinetic (tubes) to form a frequency dependent filter. There is well published theory on the subject, modeling the accumulators as capacitors and the kinetic energy storage as inductors and then using loss-less electrical circuit design methods to get the desired behavior. A loss-less design is desirable for exhaust systems because it will produce less back pressure.

This theory has a basic flaw, as published by an ATT researcher who was trying to make a better filter for the microphone in telephones. This flaw is that acoustic waves do not adhere to a planar behavior and planar waves are assumed in the acoustic filter model. The researcher converged on the following technique to solve the problem which might be applicable to exhaust system design in order to get more rumble and less shrill out of the note:

Both tubes and cavities were made from irregular shapes. The researcher use a random shape generator and did not try anything simpler. The components he used were only random shaped length wise. This technique yielded the results that were sought: a small stack of disks with a sharp low pass cutoff at 3.2kHz.

So then the question is if anyone has tried making an exhaust system from such roughly shaped parts? Also, some control over the sound of an exhaust system should be possible by simply using a series of different length and diameter pipes.
 

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Discussion Starter · #10 ·
Inserts work on motorcycle exhausts because they are inserted basically directly into the exaust system, providing return path of the
exhaust gases back into sound deafening structure or into packing....on cars inserts would really just reduce the diameter of exit pipe, probably providing zero attenuation beside chocking the engine...pretty sure that is why I have never seen a car exaust with inserts but many motorcycle exhausts have that option
Having spent some time studying rigid acoustic filters, the general idea is to use a series of energy storage devices: accumulators (cavities) and kinetic (tubes) to form a frequency dependent filter. There is well published theory on the subject, modeling the accumulators as capacitors and the kinetic energy storage as inductors and then using loss-less electrical circuit design methods to get the desired behavior. A loss-less design is desirable for exhaust systems because it will produce less back pressure.

This theory has a basic flaw, as published by an ATT researcher who was trying to make a better filter for the microphone in telephones. This flaw is that acoustic waves do not adhere to a planar behavior and planar waves are assumed in the acoustic filter model. The researcher converged on the following technique to solve the problem which might be applicable to exhaust system design in order to get more rumble and less shrill out of the note:

Both tubes and cavities were made from irregular shapes. The researcher use a random shape generator and did not try anything simpler. The components he used were only random shaped length wise. This technique yielded the results that were sought: a small stack of disks with a sharp low pass cutoff at 3.2kHz.

So then the question is if anyone has tried making an exhaust system from such roughly shaped parts? Also, some control over the sound of an exhaust system should be possible by simply using a series of different length and diameter pipes.
Lockem! You the Dos Equis Guy?

Anyway, what I was wondering was if One of the aftermarket exhaust venders would put some time into designing an insert that would allow you to return the car to being as quiet as it is when stock.
 

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Lockem! You the Dos Equis Guy?

Anyway, what I was wondering was if One of the aftermarket exhaust venders would put some time into designing an insert that would allow you to return the car to being as quiet as it is when stock.
No, he's Sheldon.>:) The term for motorcycles is "baffles".
 
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