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Weight of Wheel/Rims vs. MPG

Discussion in 'Prius c Fuel Economy' started by 88Keys444, Aug 31, 2019.

  1. 88Keys444

    88Keys444 Junior Member

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    Yeah and the design might change the aerodynamics as well. I'm assuming the weight reduction would still be beneficial.
     
  2. Leadfoot J. McCoalroller

    Leadfoot J. McCoalroller Senior Member

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    Yes, I expect the net weight loss to help overall as well, though it may be undercut somewhat by the wider contact patch. Steering is going to be very responsive, even twitchy.
     
  3. Mendel Leisk

    Mendel Leisk Senior Member

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    When I google my:

    Corolla steel rim, part no: 42611-02471

    This link says they are 22 pounds:



    (Amazon link, won't display for me unless I turn off my Ad Blocker.)

    Maybe they're talking shipping weight or something? Something not adding up. I'd really recommend you weigh them yourself.

    Addendum: yeah, that's shipping weight:

    upload_2019-9-2_13-42-17.png

    Maybe the same in your case??
     
  4. Leadfoot J. McCoalroller

    Leadfoot J. McCoalroller Senior Member

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    Does your big Prius use the same wheel as OP’s Prius c?
     
  5. PriusCamper

    PriusCamper Senior Member

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    Yep... The amount of friction from larger tire surface area to weight ration could easily put you 5mpg lower than you currently are. Changing tires and wheel size is almost always a disaster for MPG. As I said before, so long as you aren't changing the wheel and tire size lighter wheels will boost MPG.
     
  6. Leadfoot J. McCoalroller

    Leadfoot J. McCoalroller Senior Member

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    It would be good to have a few baseline measurements before installing. Compare odometer to a measured mile, speedo to a radar display or GPS etc.

    I predict that the car will accelerate nicely- slippers after roller skates feeling. The steering should be ultrasharp, bumps and road defects will be more sound effect than felt, and the final MPG… I’m doubting it’ll move much, but I think it’ll go up. A lightweight 15x5” wheel would make the difference.
     
  7. PriusCamper

    PriusCamper Senior Member

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    I'd love to make a guess on the results too... But follow up posting from people who aren't regulars hardly ever happens so it'd just be another unaswered reply... So many people get on here, get the info they need and then never share the results. It's almost like we need a standard follow up customer service type questionnaire?

    Lastly, I was under the belief that the narrower the tire, the less friction on the road, but I was corrected on here long ago by someone who explained that it's more complicated than that because you have to find the sweet spot between the friction of the type of tires with various road service types as directly relates to the weight of the vehicle as distributed but the optimum width of tire surface. Wish it was easier to calculate, but I guess if you're going for max MPG you're gonna need more than one set of tires to get it right.
     
  8. Leadfoot J. McCoalroller

    Leadfoot J. McCoalroller Senior Member

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    Hey it’s all a message in a bottle. Sometimes you get a bottle back.

    I’m guessing that Konig wheel is aimed at the Miata, I think those are the same pattern and setup. Different traction dynamics.
     
  9. 88Keys444

    88Keys444 Junior Member

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    So you guys think the extra 1.5in is going to affect it negatively? I've tried reading posts about mpg and this tire combo and nobody ever reports back. It seems like we have to be cool with our stock wheels, unless we're okay with wheel modifications for the sake of aesthetics and not optimal mpg. I'm not:cry: Especially with the stock wheel being 15x5, it's almost impossible finding a solid wheel that's lighter in weight.
     
  10. Leadfoot J. McCoalroller

    Leadfoot J. McCoalroller Senior Member

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    Very limited market- but maybe you have a way to make it pay?
     
  11. 88Keys444

    88Keys444 Junior Member

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    Perhaps. I think it's worth a shot.
     
  12. PriusCamper

    PriusCamper Senior Member

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    Well... I'd love to start a small group of us to start doing the research to come up with the best solution... It'd be ideal if we could find some friends in the used tire business too... That way we could try out different configurations without going broke on brand new that may or may not work.
     
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  13. Mendel Leisk

    Mendel Leisk Senior Member

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    Weighed my 15" steel rim (Corolla steel rim, part no: 42611-02471), with a worn Michelin X-Ice, and got 35.43 pounds. According to TireRack, a new Michelin X-ICE 195/65R05 is 19 pounds, and has tread depth 10.5/32". FWIW, the tread depth on mine is 7/32".

    Just taking the two numbers, ignoring the missing tread, and the extra balancing weights and valve stem, that's 16.43 pounds. What about compressed air; is that even a factor??

    Anyway, would guesstimate the bare rim is 17 pounds max.

    IMG_1126.JPG IMG_1127.JPG
     
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  14. 88Keys444

    88Keys444 Junior Member

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    After looking more into it, I do not see a big deal in upgrading from 6" to 6.5" with 175/65/R15. I'm surprised nobody has ANY feedback on doing this. Having significantly lighter wheels seems like such a plus for MPG.
     
    #34 88Keys444, Sep 3, 2019
    Last edited: Sep 3, 2019
  15. Mendel Leisk

    Mendel Leisk Senior Member

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    The further out from the centroid (wheel hub) the mass is, the more oomph it takes to start or stop. I think this is why low profile tires and larger wheel sizes inherently impact mpg.
     
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  16. will the engineer

    will the engineer Active Member

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    the car already gets fantastic mpg. I would reccomend for you not to worry about.

    the money saved not spending on those wheel can go to fueling.
     
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  17. PriusCamper

    PriusCamper Senior Member

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    Near as I can tell previous conversations a decade ago on here revolved around the "Volk Racing CE28 Eco Drive Wheels for Prius" and you were looking at several thousands dollars for each wheel. But perhaps times have changed? I'm seeing those wheels online under $1000 each. Of course maybe the price goes back up once you find the exact size you need for Prius? I'd have to research more to find out, but maybe someone on here who's interested in spending up to $5k on new wheels would like to try it out for us? :)
     
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  18. 88Keys444

    88Keys444 Junior Member

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    Good point. I'm just trying to personalize the car a bit. While I'm at it, I figure I'd look into improving MPG, but I won't upgrade if it will hinder MPG.
     
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  19. 88Keys444

    88Keys444 Junior Member

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    Definitely in need of some rich friends.
     
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  20. 88Keys444

    88Keys444 Junior Member

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    Just an update:

    I just purchased them online today. Will keep everyone posted:)
     
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