The science behind baffles...who knows it?

9 replies to this topic
  • Kritter

Posted February 19, 2006 - 09:54 AM


Im trying to come up with the reasoning behind, baffle tube diameter(s), tube placement, angle cut, length of tubes, etc...

Can any fill me in? My big gun came with a baffle and without the baffle it runs awesome, with the baffle it runs awesome on top but crappy down low so I have to burn my clutch up getting up the nasty hill climbs.

I have heard of people putting in baffles and gaining low end but losing top end so im curious in the design of the baffle.

Any help is apprieciated. Im going to build a few different baffles and test them but id like to know the thought process before I go cutting metal.

  • Supplicate

Posted February 19, 2006 - 11:25 AM


This might help, its more about exhaust baffles on harley's but it has some really kick ass info IMO


  • Kritter

Posted February 19, 2006 - 02:33 PM


awesome info but not what im looking for.

Im interested in noise reducing baffles that slip into existing exhaust systems...not ground up exhaust design.



Posted February 20, 2006 - 03:38 PM


All I've learned is that more baffles = more power and more noise. Less baffles= less power and less noise..(If I'm wrong someone please correct me)

I just picked up a WB e-series and have done a little bit of research on them. 8-12 discs seems to be about the average...

  • Kritter

Posted February 20, 2006 - 05:54 PM


All I've learned is that more baffles = more power and more noise. Less baffles= less power and less noise..(If I'm wrong someone please correct me)

I just picked up a WB e-series and have done a little bit of research on them. 8-12 discs seems to be about the average...

You are referring to discs...I am referring to the baffles that plug up your muffler to reduce sound...usually a sequence of tubes welded to each other at different lenghts so the exh can only exit through them and not through the opening in your muffler...

I want to know how length, diameter, surface area, angle, etc... play a role in sound and power delivery...for example if I make them all the same lenth will I increase or decrease top end or bottom end? Will it be louder or more quiet?

I wouldnt care about the science if it was adding or removing discs but I care about it since I would like to narrow down the amount of prototypes I make!

Here is a picture of the sort of thing I am referring to
Posted Image

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  • Supplicate

Posted February 20, 2006 - 07:25 PM


Just a random thought here, but couldn't this be related to runner length on carburetor intakes?

the theory that simply goes by: runner length = gas velocity


found this info doing some more searching:

Conventional Mufflers:

* Large Opening (i.e. glass packs, Vance & Hines, Thundercones, etc.)
o Good top end horsepower gains but loss of low end torque
o Very noisy

* Small Opening (i.e. ususally mechanicals baffles, Paughco, Screamin Eagel, Supertrapp, etc.)
o Good torque and low to mid horsepower gains. Very limited mid to peak horsepower
o Quiet to medium noise levels, quiet ones result in significant horsepower loss

* Hybrids (i.e. usually some sort of louvered core, Samson, Bub, etc.)
o Moderate torque and horsepower
o Medium noise levels

the more I search, the more it seems that the design aspects are all secrets to be kept after hours and hours of dyno testing prototypes.

maybe talk to Barnum's or Bajadesigns about their designs and why they did them the way they did :thumbsup:

  • Max Power

Posted February 20, 2006 - 08:09 PM


I'm out.

  • Thumpmeister

Posted February 21, 2006 - 12:02 AM


This might help. Its a little mundane for the first few pages, but it gets into the science of it a bit later.

  • Bob East

Posted February 21, 2006 - 09:39 AM


Baffles are used to silence the exhaust. They allow
the exhaust gasses to do several high to low pressure excursions before
they exit the rear of the exhaust pipe. This tends to break-up the shock
wave that would otherwise directly exit the exhaust. The idea is similar
to that used to silence firearms. The trick is to be able to make this happen
without seriously affecting the exhaust flow because that will produce
back-pressure and most of the time that's not desirable.

  • rkuckkahn

Posted February 21, 2006 - 10:08 AM


Sorry I can't help with the science, design specifics to build one, but I have a White e-series design baffel with my disc system and it works great. Maybe it's a matter of simply copying theirs. I assume they did the engineering tests, dyno, and the one they produce is the one to use.

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