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Optimum Highway Speed

Discussion in 'Gen 4 Prius Fuel Economy' started by Zardoz, Sep 22, 2017.

  1. MelonPrius

    MelonPrius Senior Member

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    I consider the source. If the charts are from Wayne, then IMO, they are accurate. He lives for this kind of stuff and takes it seriously. He won't be configuring charts while going downhill, with a strong tailwind, tailgating an 18 wheeler, etc...
     
  2. kevinwhite

    kevinwhite Active Member

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    Bob Wilson has posted a lot of good information on Priuschat from experiments he has done. You should review those:

    Such as:
    Updated MPG vs MPH chart | PriusChat

    kevin
     
  3. Munpot42

    Munpot42 Senior Member

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    There is a trade off, optimum speed for mpg vs value of your time, to me cruising at 55 on the highway would be a waste of my time.
     
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  4. KV55

    KV55 Member

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    True and this will be a different value for different people, worth noting it is average speed that counts for journey time.
     
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  5. rogerdpack

    rogerdpack Junior Member

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  6. Mendel Leisk

    Mendel Leisk Senior Member

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    The horizontal values are in kilometers per hour, and the vertical values are liters per 100 km's. With the latter lower values are better.

    upload_2024-9-25_11-21-32.png
     
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  7. fuzzy1

    fuzzy1 Senior Member

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    I just can't agree to his data collection method. It scrambles and mixes in far too much other activity. The included accelerations and decelerations render it almost meaningless for this purpose.

    The sweet spots you think you see, didn't appear in the the steady speed mpg vs mph tests run by Wayne Gerdes on CleanMPG.com, or on similar tests by a member here (unfortunately, the primary chart image was lost in a website host migration, but copies still appear elsewhere):
    Updated MPG vs MPH chart | PriusChat
     
    #67 fuzzy1, Sep 25, 2024
    Last edited: Sep 25, 2024
  8. Tideland Prius

    Tideland Prius Moderator of the North
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  9. vvillovv

    vvillovv Senior Member

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    I probably write the same thing over and over again, and boring ..... but what looks like optimal in one direction of a trip can be way off in the other direction of the return trip using the same route in both directions. So much depends on all the conditions of each route driven.