GM Truck Club
THE PREMIER CHEVY TRUCK & SUV FORUM
Founded in 2004 ~ We're the #1 Chevy Truck & SUV Forum.
Silverado & Sierra | Tahoe & Yukon | Suburban & Yukon XL | SUV & CROSSOVER
Results 1 to 3 of 3
  1. #1

    Default New Dynomax Super Turbo Exhaust Sound Clip

    I got a Dynomax Super Turbo 2.5" I/O from a friend who had it on his V6 for about a week and went back to stock. I just did a muffler swap and have about $75 invested with install included. Sounds pretty good IMO. It does have some interior drone but I'm going to be experimenting with that to see what I can do about it.

    Here's a link to a sound clip I made today.





    Last edited by GMC era; 02-25-2008 at 03:08 AM.
    1999 Sierra ECSB, 5.3L, 3.42 Locking Rear, True Flow Filter, Dynomax Super Turbo, Lund Genesis Tri-Fold, Bully Tailgate Lock

  2. #2

    Default

    I fixed the drone today. After reading some info. about drone on another site which I am a member, I decided to try this for myself. I cut about 15" off my tailpipe. (right before the bend to go out behind the wheel, so I cut out the last bend and the end) The drone magically went away. Here is the idea behind it.
    Drone in the exhaust is due to the engine driving the exhaust system at its resonant frequency. You can't get rid of it, any length of pipe has a natural frequency, but you can change the frequency (RPM) it happens at. Stock exhaust systems are tuned to put the resonant frequencies outside the normal RPM range the engine is run in. Sometimes they add resonators for this purpose. To raise the resonant frequency of a system, shorten its length. To do this, you can try tail pipes that exit by the wheel (like GM's have), or you can try a muffler with a shorter internal flow path. If you have a true dual system, you can change the natural frequency of the system dramatically by adding a balance tube. If you can't shorten the system, then you can add slightly less than one wavelength of pipe. This will also raise the resonant frequency of the system. The wavelength in a single converter system (not true dual) is a little less than three feet at 3000 RPM. Shortening the system by a foot or so will move a resonance at 2000 RPM to about 3000 RPM.
    To move a resonance, calculate the wavelength at the RPM that gives the resonance you want to move. Then calculate the wavelength at the RPM you would rather it be at. The difference is the length of pipe you need to add or delete. Add to lower the RPM, delete to raise it. If you want to raise it but you can't cut any pipe out, then add one wavelength of pipe minus the amount you calculated. This will have the same affect. If you add or subtract a multiple of a wavelength exactly, you will not change the resonant RPM.

    Wavelength = 1100 X 60 X 1/RPM X 1/4 X 1/2
    or
    Wavelength = 8250 / RPM
    Wavelength = standing wavelength
    1100 = speed of sound in air in feet per second
    60 = convert RPM to Revs per second
    RPM = RPM
    1/4 = four cylender firings per revolution (make this 1/2 for "true dual")
    1/2 = standing wavelength is half the wavelength of a "normal" wave
    1999 Sierra ECSB, 5.3L, 3.42 Locking Rear, True Flow Filter, Dynomax Super Turbo, Lund Genesis Tri-Fold, Bully Tailgate Lock

  3. #3

    Default

    My exhaust seems to have gotten slightly louder over the last couple months. I'll try to get a clip of it now.
    1999 Sierra ECSB, 5.3L, 3.42 Locking Rear, True Flow Filter, Dynomax Super Turbo, Lund Genesis Tri-Fold, Bully Tailgate Lock

Similar Threads

  1. Aero 3030XL exhaust clip
    By PIKE33 in forum Performance & Fuel
    Replies: 0
    Last Post: 06-25-2010, 06:15 PM
  2. my 4.8 ltr 40 series flowmaster exhaust clip
    By devilsalmostfree in forum Photo & Video Gallery
    Replies: 1
    Last Post: 06-11-2010, 06:49 PM
  3. My exhaust (video clip)
    By Mindi51982 in forum Performance & Fuel
    Replies: 21
    Last Post: 02-19-2009, 09:16 PM
  4. Sound clip of my new Long tube haeders and Pics
    By RockHead in forum The Coffee Shop ~ Chit Chat
    Replies: 4
    Last Post: 11-02-2008, 10:27 PM
  5. Gibson super truck exhaust
    By topwater in forum Chevy Silverado Forum (GMC Sierra)
    Replies: 0
    Last Post: 07-24-2008, 12:46 PM

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •