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Hypermiling poll: Hills

Discussion in 'Gen 3 Prius Fuel Economy' started by iOCDad, Jun 11, 2010.

?
  1. Gun it all the way up the hill trying to get to top as fast as you can.

    2 vote(s)
    4.0%
  2. Gun it up the hill until reach point where can glide/coast to the top.

    11 vote(s)
    22.0%
  3. Pulse/glide all the way up the hill.

    2 vote(s)
    4.0%
  4. Maintain same speed with no sudden acceleration.

    26 vote(s)
    52.0%
  5. Other (see response below)

    9 vote(s)
    18.0%
  1. Downrange

    Downrange Active Member

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    Depends on a lot of things. The type of hill, for one thing. Also ambient conditions, especially following traffic. Little hills call for a quite different approach than really big hills. Warp stealth is your friend (coming down). Best answer (most often the technique I select) is constant speed going up - smooth. I do try to bank a bit of momentum away prior to climbing, but it's quickly spent.
    Terrain (hills) is probably the single most important determinant in this game, once you've mastered the fundamentals. Net elevation gain or loss can be enormous here in the Appalachians. It takes some skill to determine the best approach for all these variable conditions, something I'm working hard to develop.
     
  2. Tom183

    Tom183 New Member

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    The most efficient way is to do what Bob Wilson said: keep the ICE in the most efficient range for as long as possible. The only time you would want to do EV (or the equivalent) is if you have a long descent (or if you just finished one).

    If there is no traffic, then accelerate before the hill (while keeping the RPM in the optimum range), and keep the pedal there all the way until a little before the top. Depending on the hill, you can finish the last bit in EV/glide mode to make some extra space in the battery for the descent. The hybrid system will almost always have some headroom in the battery anyway, so you don't even need to do this unless the descent is long enough to fill all that space and then some.

    For steeper climbs (or in heavier traffic), your only option is to push your foot down. Unfortunately, hills + speed will push the ICE into the less-efficient range.
     
  3. bentbow

    bentbow Junior Member

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    so it appears 3100-3300 rpm is best? I'm trying to figure out the best Pulse technique, so far nearly flooring it is working well plus people behind me appreciate it and i get up to speed faster.
     
    #23 bentbow, Mar 20, 2018
    Last edited: Mar 20, 2018
  4. fuzzy1

    fuzzy1 Senior Member

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    This chart is specific to the Gen3 engine, not reflecting changes and updates to your Gen4.

    Flooring it generally does not put the engine into a zone of near-maximum efficiency.
     
  5. vvillovv

    vvillovv Senior Member

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    Other (see response below )
    depends
    on
    the hill
    the weather
    other drivers around me
    traffic conditions
    road conditions ( if there is a road )
    amount of available light
    ambient temperatures
    if in orthodox hyper-mile mood or just quasi
    how much ev I have left and how far I need to go

    is there a time limit? can I add more as they occur to me?
     
  6. wfolta

    wfolta Active Member

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  7. bentbow

    bentbow Junior Member

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    I mean, it feels like flooring to me but I'm referring to pushing in about 2/3 to get 3k rpm.