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Prius c has worse mpg than Gen III on Fuelly

Discussion in 'Prius c Fuel Economy' started by Farfle, Jul 9, 2014.

  1. Brad K

    Brad K Member

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    the Prius C proably only gets 41-43 mpg at 80 mph using cruise control on non-flat surfaces. It can get about 48-51 mpg at 70 mph. And 60 mpg at 60 mph. So how does that calculat into 46 EPA HWY
     
  2. fuzzy1

    fuzzy1 Senior Member

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    Did you read the article? The EPA and CAFE test cycles are not constant speed, but have specific speed vs. time profiles with multiple stops.

    Raw EPA figures, before the computations and rounding for the Monroney stickers, are posted at Download Fuel Economy Data. For the basic highway test, the 2015 'c' got 69.5848 mpg, vs. 69.6895 for the Liftback. At the moment I don't see the results of the other three tests, so don't know if they used the real 5-cycle or adjusted 2-cycle method, or exactly how the larger gap appeared.

    Note that to get the 54 mpg rating you suggest (or 53.5 before rounding), the raw highway test cycle result must be at least 74.31 mpg, under the old (1985-2007) EPA label rules. The under new rules (2008), an even higher test result is required to get that final label number, but the extra formula adjustments add more complexity.
     
    #102 fuzzy1, Apr 29, 2015
    Last edited: Apr 29, 2015
    Brad K likes this.
  3. skayaks

    skayaks Active Member

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    Maybe this is old news, but I just noticed that Fuelly has a nice (new?) feature that presents results for each model year of a vehicle based on all fill ups for that model and year, but with outliers stripped.
    Since there were always some wacky tanks in the mix - like a Tacoma magically getting 70 mpg on a recent fill (I invented that example) - it makes it easier to compare average FE for different vehicles.
    PIPs are still blended with Liftbacks but there are a lot of outliers stripped in that case.
     
    ftl likes this.
  4. Andyprius1

    Andyprius1 Senior Member

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    On my 2013, Prius C I have record mpgs of 97, 98, and 99.9.
     
    #104 Andyprius1, Jun 25, 2015
    Last edited by a moderator: Jul 13, 2015
  5. vinnie97

    vinnie97 Whatever Works

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    How many miles are covered in each of those records, though? I'm going to speculate only a couple.
     
  6. priusCpilot

    priusCpilot Active Member

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    The C will win in the city easy over the Liftback.

    Once your going past 69mph is were the C starts dropping over the Liftback based on tests.
     
  7. PeterHaas

    PeterHaas Member

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    Perhaps that is why, after two months of ownership of a 2014 Prius c One purchased brand-new, and putting about 1,100 miles on it, I bought a lightly used 2012 Prius Liftback Two.

    The c is fine within my smallish city (population about 50,000), but the Liftback is better in every way outside my city.

    In my case, the Liftback is, hands-down, a better value.

    I enjoy driving the Liftback under all conditions. I enjoy the c only as a distant second choice.
     
  8. priusCpilot

    priusCpilot Active Member

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    For me it's the opposite. We also have a Prius plug-in in my family and I prefer the C. Mainly because I prefer the dominion C over the heavier plug in. Much more responsive and tossible.
     
    #108 priusCpilot, Jul 13, 2015
    Last edited: Jul 14, 2015
  9. orenji

    orenji Senior Member

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    Well, I like my C and will keep it for a very long time. It does everything I expected at the time of purchase, and more, now that I have had it for several years. Cars are like tools, you need to make sure you buy the right tool for the job. Sometimes you need more then one tool in the garage.(y)
     
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  10. Dimitrij

    Dimitrij Active Member

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    in another thread, there was somebody who reported 99.9 mpg over 500+ miles. He had done this to find out what the limits were and to prove the point, so not in the normal day-to-day driving conditions (I think his average mph was somewhere between 20 and 25, so it will have taken a whole day of careful driving).

    On occasion, in good weather and in no hurry I have clocked in excess of 90 mpg, driving across our city for 5-10 miles, but even without trying too hard it's in the upper 80s.
     
  11. vinnie97

    vinnie97 Whatever Works

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    Yes, and he was hypermiling for the sake of a competition here (username of ufourza or somesuch), but getting over 90+ mpg beyond a few miles is atypical. I would wager I probably have close to your average mpg on my 2012 C. Traffic (stoplights specifically), terrain, and weather can all result in significant hits in fuel economy, I've found (perhaps more so than the liftback).
     
  12. Anthro

    Anthro old member

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    Exactly! (I suspect many people ignore the smaller frontal area of the C when considering the meaning of the .28.)
     
  13. cyclopathic

    cyclopathic Senior Member

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    Actually Fuelly shows higher MPG for C?
    This is a printout from your fuelly links, one year later
    C-mpg.png GenIII-mpg.png
     
    orenji likes this.
  14. Oldwolf

    Oldwolf Prius Enthusiast

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    My C is getting higher mpg than my Gen II.
    See my Fuelly results below.
     
  15. usnavystgc

    usnavystgc Die Hard DIYer and Ebike enthusiast.

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    The C will beat the Gen II hands down.
     
  16. orenji

    orenji Senior Member

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    The C is the winner :D:D(y)(y)
     
  17. cyclopathic

    cyclopathic Senior Member

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    C MPG seems to suffer more from low temps and break-in. My C averaged 42MPG for 1st 130mi. With 15.5k on the clock it is at 59.3 indicated for last 5500mi now. So I wouldn't be too concerned with new year model MPG low at the beginning.
     
  18. Oldwolf

    Oldwolf Prius Enthusiast

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    Even though Fuelly calculates 55.5 mpg for my C, the computer consistently tells me my mpg is averaging 57+ mpg.
    Both my Prii computers are optimistic.
     
  19. cyclopathic

    cyclopathic Senior Member

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    On mine the diff ~2-2.5MPG real vs calculated. This is pretty normal for all Priora and all cars in general.
     
  20. Oldwolf

    Oldwolf Prius Enthusiast

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    I've kept track of the errors on both cars since I have owned them.