Dual vs. single exhaust:

Discussion in 'Trucks [ Eighteen Wheelers ]' started by Powell-Peralta, Apr 28, 2011.

  1. Hammer166

    Hammer166 Crusty Information Officer

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    Mainly because truck engine builders rate their engines on a test stand, with 'x' inches of intake restriction and 'y' inches of back pressure. If either of those numbers is exceeded, HP drops and BSFC increases.
     
  2. Powell-Peralta

    Powell-Peralta Road Train Member

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    i'm basically trying to figure out which would be better for team operation.

    i'm thinking that all the exhaust, in most applications, comes off one manifold then if dual exhaust would split after the "Y".

    More mufflers=less noise since it's coming originally from one manifold?
     
  3. Les2

    Les2 Road Train Member

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    Keep in mind duals will sound louder cause one pipe is closer to the driver in that application.
     
  4. BUSY

    BUSY Bobtail Member

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    You can split a manifold on a normaly asp engine but you cant running out the turbo beating1
     
  5. BUSY

    BUSY Bobtail Member

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    looking at a single exhaust typ.its mounted on the pass. side releaving the operator the noise
     
  6. Powell-Peralta

    Powell-Peralta Road Train Member

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    i guess another way to rephrase the question is:


    If you took a truck with single exhaust and added a dual to it----using the exact same muffler and pipes as the original side, would this then be quieter than single exhaust?

    i'm thinking in theory yes. More mufflers= more noise reduction.
     
  7. magnum2

    magnum2 Light Load Member

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    let me ask you all this, those who know : what are pro's and con's of going with the one inch bigger exhaust from the turbo? I have the 2006 isx and after the Vgt there is the reducer to the smaller exhaust, vs the Vgt exhaust size. My pipe is beginning to rust through so, I was thinking about changing the pipe to the same size as the Vgt exhaust port, diameter wise. Should I do it or not? Why? Why not? Thank you.
     
  8. Hammer166

    Hammer166 Crusty Information Officer

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    The reason for the smaller outlet pipe is to increase exhaust back pressure so that the egr functions properly. I'd say you'll likely get a warning light unless the egr is already non-functional.
     
  9. magnum2

    magnum2 Light Load Member

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    Besides the egr issue.
     
  10. Hammer166

    Hammer166 Crusty Information Officer

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    Open it up! Anything that makes a motor breathe better makes it more efficient. After saying that... I don't know if Cummins uses a map or a pressure sensor to control exhaust manifold pressure. If the ECM senses pressure, it could attempt to adjust the turbo to increase the exhaust manifold pressure, defeating the gains made by freeing up the outlet.