4 into 1 vs 4-2-1

Discussion in 'The Perfect Line and Other Riding Myths' started by Colorado_Rider, Sep 6, 2013.

  1. Colorado_Rider

    Colorado_Rider Banned

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    Not porn, exhaust.:lol3 Most of us know the theory, but will I notice a difference on a mildy tuned engine such a my Honda 919? Or more specifically if I put a 4-2-1 header pipe will there be a loss of low end power?
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  2. ThumperStorm

    ThumperStorm Long timer

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    Might not be the right place to ask. Maybe in Garage or Road Warriors?
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  3. Maxyb

    Maxyb Falling over slowly

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    4-2-1's are made for a broader range of torque, 4-1's are made for better peak. So, no there will not be a loss of low end power, there will be more of it (provided the 4-2-1's are tuned like that).

    You probably won't notice it, there may be 1-3% difference, but the butt dyno won't really be able to tell
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  4. anotherguy

    anotherguy unsympathetic

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    After tuning the 4:2:1 will deliver a fatter midrange at the expense of a few top end ponies. Be sure to have it tuned on a dyno or leave the bike alone. 4 cylinders,Honda in particular are finicky when installing a full exhaust. Middle RPm part throttle is where the difference is most noticeable. Worth the effort if you're going to keep the bike. Not cheap.
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  5. Colorado_Rider

    Colorado_Rider Banned

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    Prolly right, can someone move it?
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