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88 octane - loss of MPG

Discussion in 'Gen 3 Prius Main Forum' started by Steelerfan2018, Jul 16, 2021.

  1. fuzzy1

    fuzzy1 Senior Member

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    You need to specify model year when saying which E-level a Prius can use, because it has changed over time. Your 2017 can use E15, but OP's 2011, like my 2012, is rated only to E10. My gas cap is specifically marked against using E15-E85, with the red circle-and-slash symbol.
    Arco (at least before being bought out by BP) was specifically aiming to be a low price leader. The other majors, at least in my region, where aiming to be a bit more upscale. I have chemical engineer relatives working for or with several of them.

    Being a low price leader does not prevent a company from meeting Top Tier requirements. Arco/BP joined a long time ago, even Costco has joined.
    It could be in the engine, as I had in a couple long-ago cars that were designed for 87 but accumulated some problems with age.
    Not always true, at least according to one of my refinery relatives. At least back several decades ago, the 87 blends she produced typically had slightly higher energy content than her 91 blends. The 91 could not take as much of certain high energy but knock-prone hydrocarbon components. But differences were refinery- and batch-dependent, and consumers will not have access to the specific details. Batch differences arise because they have different amounts of the various fuel components available at any given time, are trying not to waste anything, and there are multiple ways to reach a final product that meets the fuel requirements.

    Do beware that fuel property requirements have since changed, and refineries may have changed processes too, so answers could be different today.
     
    #21 fuzzy1, Jul 18, 2021
    Last edited: Jul 18, 2021
  2. privilege

    privilege Active Member

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    see my post again, there is corn gas, and real gas. I'm referring to real gas (not corn mixed in) in the "non ethanol" octanes.
     
  3. Yaesu

    Yaesu Member

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    I am surprised that the OP is getting such poor fuel mileage, regardless of which fuel he is using. Are you relying on the computer in the vehicle for your fuel mileage calculations or are you manually determining the fuel mileage? We have two Prius' and normally get around 50 mpg (manually calculated) with both of them. AC running almost all of the time. However, cold weather and wet roads reduce our mileage. Only high compression engines or those that have massive carbon build up in the combustion chambers need to use high octane fuel.
     
  4. Grit

    Grit Senior Member

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    Had the same debate with 2 other people that went for 3 pages, they said e15 was a-ok.

    47C06958-586F-48CB-95C8-B9FBC097D436.jpeg
     
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  5. Rmay635703

    Rmay635703 Senior Member

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    E15 is rarely E15, depending on local regulations, heat and weather (higher percentage hits evap regulations in some areas) and other constraints
    E15 can be e10.5 to e14.9999
    The same is true of e10, it can be less ethanol hence the “up to moniker”

    Back to the Gen 1 some have ran e50 mixes for extended periods without cell, leaks or failures.

    Only issue was a obvious loss of fuel economy
    (e50 is very different than e15)

    Even our local TVs Bob had a historical thread on this subject with data.
     
  6. Pulse07

    Pulse07 Active Member

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    I don't know what "corn gas" is, hopefully no one is putting corn in the gas tanks. E10 in my parts is "real gas" , you wont be able to find a station in my metropolitan area that is not E10.
     
  7. sam spade 2

    sam spade 2 Senior Member

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    So.....you prefer to be paying Big Oil subsidies ??

    When was the last time that a big corn spill caused a million dead fish ? :eek:
     
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  8. sam spade 2

    sam spade 2 Senior Member

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    Unless it also contains a significant amount of "non-gasoline" fuel that has less chemical energy.
     
  9. PaulDM

    PaulDM Active Member

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    In the UK gen4 (2016-present) is only rated for E5 or E10 ( introduced here last month)
     
  10. fuzzy1

    fuzzy1 Senior Member

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    Don't forget the fossil fuels burned to produce that corn. And the fertilizers and insecticides applied to that corn, some of which wash out of the fields and into the fish-bearing waters, both with detrimental results.
     
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  11. privilege

    privilege Active Member

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    e10 is marked e10 because it isn't pure gasoline. kind of simple, ain't it ?
     
  12. privilege

    privilege Active Member

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    1) yes. I don't want to pay more for less efficiency. adding corn to gasoline decreases the fuel efficiency and costs more that's wasteful x2.

    2) big corn spill.... you mean like the constant flow of herbicides, pesticides, fertilizer, running into the streams ? I know, it doesn't look like an oil slick so it's harder to spot, but it's happening and accepted, ALL THE TIME.

    oh ya, and while they were farming up that wonderful corn to dilute the real pure gasoline... they were burning more diesel to do it. and using more water. all of which were taxed , again.
     
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  13. sam spade 2

    sam spade 2 Senior Member

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    I will NOT get into an extended argument about this.
    Ethanol is NOT the evil work of Satan. It just is NOT.
    It is not perfect either.......and petroleum fuels are FAR from perfect too.

    YOU and many others have fallen for the brainwashing propaganda from big oil.
    Refining oil ALSO uses huge amounts of energy.......on and on.

    How about just giving it a rest and trying to resist the temptation to bash ethanol every chance that you get ??
    6 million farmers will thank you.
     
  14. ASRDogman

    ASRDogman Senior Member

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    You know, you might have just gottan a bad tank of fuel.
    It seems to be best to stick to name brand fuel. And to what the recommended fuel for your engine.
     
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  15. Grit

    Grit Senior Member

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    all true. Which ever political candidates panders to the “corn states” the most, by putting policies to put corn in everything and bring corn subsidiary programs, and anything to create demands for corns, politicians will earn corn votes.
     
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  16. fuzzy1

    fuzzy1 Senior Member

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    Nope. There are only about 2 million farms in the U.S., and only about 300,000 of them grow corn.

    And as a sort-of farmer myself -- not the actual current owner, but part of the family still providing labor because dad is too old and infirm to do it anymore, I just returned from a two week harvest work shift -- I have no problem with him bashing corn-based ethanol. We ought to defer ethanol mandates until cellulosic ethanol becomes viable.
     
    #36 fuzzy1, Jul 20, 2021
    Last edited: Jul 20, 2021
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  17. sam spade 2

    sam spade 2 Senior Member

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    Other parts of the world use FAR more ethanol fuel than the US does.....but I imagine that the source varies widely.

    Then......if ethanol really is EVIL like it is made out to be, the source doesn't really make much difference.
     
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  18. privilege

    privilege Active Member

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    1 I'm genuinely interested in this part. I like to think of myself as not easily convinced, but if you have some propaganda/brainwashing to point out about big oil, I'm all ears, no sarcasm or malice involved here at all.

    2 agreed.

    3 I only bash it when other people say ethanol is a totally acceptable when compared to real gasoline. because it isn't.

    4 if they could stop accepting tax money for producing crops (like corn fuel) I would definitely thank them for it.
     
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  19. fuzzy1

    fuzzy1 Senior Member

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    Such as?

    upload_2021-7-21_13-49-55.png

    That doesn't follow at all. A given amount of fossil fuel can produce far more cellulose than corn for raw feed stock into an ethanol factory, potentially making for a much more favorable energy balance. Though until a viable cellulosic process is developed and settled, we just won't have a decent comparison.
     
  20. sam spade 2

    sam spade 2 Senior Member

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    The oil companies immediately lost 10% of their market when E10 was mandated.
    But history shows that they always tell the absolute truth......doesn't it ??

    And almost 100% of the bad publicity about ethanol can be traced directly back to the Oil Industry lobby.

    Would you prefer the other additive to improve tailpipe emissions.......the one that causes cancer ??
    Or would you suggest not worrying about air quality and climate change ??

    It's been REALLY hot here lately.