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

  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 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.
     
  2. jcsd
  3. Ranger Mike

    Ranger Mike 1,562
    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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