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Chamber design (mufflers). I'm stuck, please help!

  1. Nov 11, 2012 #1
    my lonesome have been working on a set of mufflers that don't sound like fecal matter. I am having a difficult time finding just the mufflers (race mufflers). I DO NOT want an entire exhaust system. I do have the capability of fabing up mufflers, I have custom made equal length headers to an x pipe thus far. I DO NOT want the mufflers to have those two little connections keeping them together. I will be making this a side exit.

    The motor is a carbed 5.5 lt small journal sbc. Should be able to make power to 7800 or so rpm.

    I am looking for the highest frequency/note/tone/pitch I can get. I very much enjoy the higher, crisper, cleaner sound the euroapean v8 makes. I hate with a passion the rumble of the harley/dumptruck American v8. I have heard flowmasters on these cars. I don't know if it was the particular flowmaster series or what. But that m3 was a dumptruck. I am trying to avoid that.

    Sounds like a chevy small block doing a dyno pull to me...
    htt p: //w ww.youtu be. com/watch?v=Y-mGGf5Ncx8

    h ttp://ww w.yout ube. com/watch?v=5BhxWH9Dg_M]BMW E92 M3 Eisenmann race exhaust - YouTube[/url]

    amazing high frequency sound
    htt p://w ww.youtube.co m/watch?v=SbT0IqFIfnc]iPE Innotech E92 M3 Evolution Valvetronic Exhaust System F1 Sound - YouTub

    h ttp://www.y outube.com/watch?v=n_n8HiJzA6A]BMW M3 iPe Valvetronic Exhaust Sound (Drive By, Downshift, Rev) - You Tube

    Here is a cutaway of a corsa muffler.

    ht tp://s805.b eta.photobucket.co m/user/Phastek/media/March%202010%20Show/Corsa1.jpg.html?filters[term]=recent&filters[primary] =images

    I am rather sure that the chambers in the muffler can be designed as such to reflect frequencies to cancel out the unwanted frequencies. I just can't find the math anywhere to determine the dimensions of the chambers.

    I am working with 17.9 inch long primary tubes that are 1 and 5/8 in diameter, they go into a 2.5 inch collector, that then goes into a 3 inch x pipe, that will then go directly to the side exit mufflers. I am keeping it as short as possible to help retain the sound I am after.

    This is what I am avoiding.
    htt p://ww w.youtube.c om/watch?v=klmAQFh1l-E]Magnaflow Exhaust on a Chevy Truck - YouTube

    Same motor different car different mufflers...
    http://w [Broken] ww.youtube.com/watch?v=IVWZMKMmjMQ

    So does anyone know how to design the muffler to achieve this? Or designing a resonator to do this? Or simply the chambers inside the muffler to do this?

    I am so stuck. Also I don't think a helmholts resonator of any kind will do the trick. that would only cancel out the freq. I think this is more like a musical instrument where the sound entering is not going to be the sound at the bell of the horn coming out.
    Last edited by a moderator: May 6, 2017
  2. jcsd
  3. Dec 18, 2012 #2

    Ranger Mike

    User Avatar
    Science Advisor
    Gold Member

    do you have the engine running? About the only way to " tune " the exhasut to a particular freq. is to fabricate a muffler/resonator that can be adjustable length and experiment. By shortening or lengthening th baffle arrangment to housing length you should be able to find the note you want.
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