I searched and couldnt find the answer to my question.

Could someone tell me how the twin loop affects exhaust flow compare to the very straigt style of the Spoon N1(for example).

I am just wondering how this setup logically can improve air flow(not that I'm am saying it cant).

Lax - Who wonders about many strange things at 1 AM EST


[Modified by Lax R man, 5:45 AM 6/25/2001]

 

Okay, the simple explanation is that exhausts must have certain silencing characteristics in order to be streetable and tolerable to the everyday driver (ie, those that are driving next to you). Most aftermarket companies achieve this by creating a series of chambers inside the muffler that silence the car's exhaust sound. The Mugen exhaust silences by the use of the "twin loop", which effectively cancels the sound waves. This enables the exhaust to be quiet, as well as less restrictive (silencing through the use of the pipe versus chambers in the muffler).

Here is King Motorsports' description:
"Silencing characteristics and the quest for exhaust efficiency: the two requirements imposed on exhaust systems have a contrary relationship, and in practice it is extremely difficult to achieve both. At Mugen, we have continued to employ the straight configuration, with the design philosophy that low exhaust pressure must be provided, and that reducing exhaust resistance is an important part of the ideal exhaust system. The straight configuration is widely used in racing, and is ideal because, as the name suggests, it provides low exhaust resistance. However, large silencers are generally required, as there may be problems with mid to low frequency band silencing and scattering of sound absorbing material such as glass wool with the straight configuration. Incidentally, the inverted multi-layer expansion-type silencer widely used by automobile manufacturers provides stable silencing performance, as the sound passes trough several divided silencer chambers, but involves the disadvantage of some output loss and is larger and heavier than other silencers. As a result of our quest for the ideal design for racing engines, Mugen developed the "twin loop-type silencer," in which the pipe is twisted into two loops and passes straight through the silencer twice. This could be considered the ultimate arrangement, combining the concepts of "absorption" and "intervention" in an ingenious manner. It surpasses normal systems in power and torque over the full range, and provides the required silencing and the clear Mugen-Honda sound."

 

Thank You very much Bob....That's EXCATLY what I was looking for.

 

Your welcome .

 

Now if they could only make the twin loop LESS EXPENSIVE....oh i guess that's why its mugen

 

But remember, it IS a catback. It's not like your paying $975 for just the muffler.

 

But it would be BETTER if they sold it as a rear section only. The USDM b-pipe is too restrictive (choked down to mate to USDM cat). I had one. THough I never put it on my R, If I had, I would have had a custom 2.5" b-pipe made and trached the *beautiful* Mugen one.

BTW, the Mugen twin loop flows VERY well. TODASi only lost ~3 whp on the dyno with open header vs. 2.5" b-pipe and Mugen Twin loop (Si version). He doesn't have a cat. HTH,

adios,