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Technical thread hijacked (request deletion or move)

Discussion in 'Gen 4 Prius Main Forum' started by bwilson4web, Dec 3, 2015.

  1. bwilson4web

    bwilson4web BMW i3 and Model 3

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    There are three things that would complete our understanding of the 2016 Prius:
    1. MPG vs mph chart - so we can tell what speeds give what fuel consumption rates
    2. OEM calibration constant between tripmeter distance and GPS or mile markers
    3. Maximum acceleration test to understand Prius net power

    When we took delivery of our 2010, on the way home I did a series of 10 mile, bi-directional, cruise control speed managed tests to map out MPG vs mph:
    [​IMG]

    • bi-directional and average two runs - this takes out the elevation and wind effects
    • as many different speeds as possible - minimum, 25 mph and your comfort highway speed
    Measure the difference between a tripmeter and GPS or mile markers for at least 20 miles, ideally, 100 miles. Speed and dry weather does not matter as this is for the calibration correction factor. Just try to do it in one driving segment.

    It would also be useful to do a maximum acceleration from a standing, brake-start, with an OBD recording scanner. Alternatively, a recording GPS including a nuvi would substitute for the OBD. You'll need a flat road with little or no traffic in the 60-80 F range. Low wind or cross-wind are desirable but not critical if documented relative to the direction of the test. Hold the car with the brake and floor the accelerator. Wait until the car is steady, not changing, one last traffic check and release the brake. Continue the run to over 60 mph or as high as you feel comfortable. Then share the data including model, fuel level, and passenger/driver weight.

    Bob Wilson
     
  2. GasperG

    GasperG Senior Member

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  3. bwilson4web

    bwilson4web BMW i3 and Model 3

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    I had seen it before:
    Now that VW diesels sales are suspended, perhaps Wayne might do the right thing.

    BTW, did you ever see these three examples:
    [​IMG]

    [​IMG]

    [​IMG]
    Notice these charts span lower and higher speed ranges.

    BTW, here another chart you might have seen:
    [​IMG]
    We had to play some math tricks with the raw data to get a continuous function to calculate the net power. More importantly, the points above 85 mph suggest something interesting is happening there. Still, it is good practice to make multiple measurements to take out human errors. For example, I think it was @Tideland Prius who posted some dyno charts with multiple runs.

    Such charts have a practical application for driving stunts:
    [​IMG]

    My favorite examples come from:
    Gen 3 Prius Fuel Economy | PriusChat

    Bob Wilson

    Upon further reflection:
    I would have more respect for your posts if you would independently validate Wayne's results and share them here. It would raise your technical qualifications above a 'copy-and-paste' follower to someone who actually has a clue about what they are posting.

    Bob Wilson
     
  4. ksstathead

    ksstathead Active Member

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    Bob, what do you question about Wayne's methods? He's done many dozens of these to an exacting standard. No one is saying there are not other (more?) exacting standards, but I've never found one his speed vs mpg charts that failed to show a materially correct picture of a car's potential at the tested speeds. Is it the linear lines he draws between his data points, or what.

    Also, when you say "Now that VW diesels sales are suspended, perhaps Wayne might do the right thing.", what does that have to do with his mpg charts and what thing did he do wrong? You probably know he has a 2012 PIP and no diesels in his stable?

    Glen
     
  5. bwilson4web

    bwilson4web BMW i3 and Model 3

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    Have you brought any original content?
    PriusChat has a wide community of members and the ones I can respect bring original content, not just 'cut-and-paste' from one source.
    Just remembering how long he has resisted owning a Prius and time spent advocating (advertising) fuel efficiency of non-Prius cars. I understand he needs to earn a living and I'm OK with that but I also remember the public humiliation of a MA Toyota dealership.

    The dealership had sponsored an efficient car rally only to have Wayne's team insist non-Toyota cars compete and then award prizes to the non-Toyota cars. In effect, killing off the last of the fuel efficient rallies.

    You do remember that some of Wayne's November 9th, Press Test Drives, was 'leaked' before November 18. If a man is not as good as his word, trust is lost.

    So yes, I'll take any original content by a 2016 Prius owner or any of the trustworthy press who get a chance to more throughly test the 2016 (CR excepted *.) Credible people who keep their word get my respect and attention. The others can join my 'Ignore User' list.

    Bob Wilson

    * - Several years ago after the weak 2010 Prius review, I went to the library and using back issues of CR, evaluated their numerical score versus the codes of the fields they mark. What I found:
    • highest rating for 'driver' comfort
    • minimum 10.1 seconds required in sprint or lose 15 points
    • nothing for fuel efficiency
    • their internal MPG has as much credibility as their quality of their testing documentation
    Install a 'comfy chair' and CR will forgive much:
    [​IMG]
     
    #5 bwilson4web, Dec 3, 2015
    Last edited: Dec 3, 2015
  6. ksstathead

    ksstathead Active Member

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    No, you could say I haven't, and yet I've been contributing in my own way for 8 years. I don't claim to be an engineer, or to be willing/able to do the things you do. I don't challenge your value here, or equate mine with yours.

    Didn't think I was striking a nerve, but you seem to denigrate Wayne without a stated reason. Now you've implied that two others including me should not be allowed to post here unless we are conducting tests you deem valid. What is the value of your work here if others cannot benefit? Why should others do work already done (by Wayne, for example)?

    Edit: after I posted the above, and before I posted the following, Bob provided his reasons for discounting Wayne's work. My two posts were combined after the fact...

    thanks for the response.
     
    #6 ksstathead, Dec 3, 2015
    Last edited: Dec 3, 2015
  7. bwilson4web

    bwilson4web BMW i3 and Model 3

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    No problem:
    *PLOINK*

    Bob Wilson