Has anyone ever tried one? They're pretty big in the inline 4/6 world. I would love to hear one on a Ford 6!
Basically a system where the exhaust gases pass trough the muffler twice, supposedly it the quietest performance muffler you can use. there's many variations of them: single muffler type: dual muffler type: The coolest one i've seen are the guys that turn the V8 dual inlet/dual outlet mufflers into a twin loop muffler for a single exhaust! yes the "+50hp" is a joke from another forum, but the principle is correct.
They look funky but no different to having 2 mufflers inline. The drawing above would wreck flow- you cant have gas flowing one way then double it back on itself flowing back the other way through the same chamber. That would wreck performance. Those X mufflers could work but would have to be used like X pipes and have both sides flowing the same direction! I do very much like the look of the first image though.....
From I can gather... They seem to be quieter than most of the fart cans that kids throw on their mother's Civic.. I wonder... It basically is a muffler with a pipe that "loops" back into itself... I don't see how that could be beneficial? Maybe I'm just not understanding the idea behind it... Is it like a "mini" x-pipe?
The key here is that they're quiet, they're are not the best flowing muffler out there by any means. and lets face it most inline motors don't sound good with performance mufflers Like the magnaflow i had on my I6 sounded like a tractor...flowmasters and turbos sound marginally good.
Hmm... I may have to be the guinea pig and get one for the Maverick... Gimme a few months and I'll have a video :Handshake
i agree with your theory. But im not an exhaust expert so i have no clue if it work or not. But several autocross guys use them thought And They look really cool
this is the description for this muffler "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."
It looks to me like the design has some merit .... it would be using sound pulses hitting the muffler at different times to cancel others out. For example ... A pulse enters the muffler, some of it goes into the chamber and most of it carries on into that loop. By the time it travels that extra distance and gets back in via the second entrance, you have created a shift in the timing. The same exact tones hitting into each other, but with the shifted timing ought to really degrade each other. Add later pulses and tones into the mix, and there should be a lot of disruption. Some other performance mufflers use a similar idea internally... two paths, one straight and one has some bends to it. The sound waves enter the shared chamber at different times ... just milliseconds apart ... but that is enough for a mild noise cancellation. This design looks like it might stretch that timing out. I wonder how they would sound on a V6? Might look further into these...
While it may be quieter (don't really know) it is deffinitely more restrictive than two straight-through mufflers. If I could get away with it I would run without mufflers at all because by absorbing or cancelling sound they interupt the sound pulses that can benefit the scavenging effect of the exhaust. Those "fart can" mufflers are actually better on small engines as far as scavenging is concerned because they don't eliminate the sound pulses until the exhaust exit is reached. You can use the entire exhaust system to tune for the best performance. If all you want to do is have a free flow exhaust without the tuning of an "engineered" exhaust then use big headers and bigger pipes through a really big muffler and out big pipes from there. You won't get much scavanging but your exhaust will be cold when it reaches the exit and the noise will sound kool. I prefer a tuned exhaust that adds Torque/hp through the entire power-band. That is why, when it is important to me, I do the math to get the correct size and length headers and then tune the length of the collector, the length to the muffler (properly sized) and the length of the whole exhaust system and end it with a good extractor tube. The gasses are still warm and it is still getting the pulses back to the engine to provide better volumetric efficiency. It ain't easy but, for me, it is worth the time.
