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Rear Wiper Aerodynamics

Discussion in 'Gen 3 Prius Accessories and Modifications' started by Jehan Ansar, Feb 9, 2019.

  1. Jehan Ansar

    Jehan Ansar Junior Member

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    Hello, This has been bothering me ever since I bought a prius last month. I like to know if the rear wiper affect the aerodynamics of the car. Would removing the rear wiper improve fuel efficiency and reduce drag score? I'm tempted to remove it so please let me know, thank you
     
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  2. Pluggo

    Pluggo Senior Member

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    The short answer is yes, it would have to improve aerodynamics when you remove a bumpy thing like the rear wiper. How much improvement? Well, that's another matter altogether. It would also improve aerodynamics if you would apply smooth tape to the open joints around all your doors and find some very flat, plain wheel covers for all four wheels. Strictly speaking, not everything you can do to improve aerodynamics would be legal. You could also remove outside mirrors and front wipers, too. Don't forget to take down the radio antenna and remove the door handles. You will be climbing in and out of the car through the window like a racecar driver.
     
  3. ASRDogman

    ASRDogman Senior Member

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    Of course, how would you get the door and windows open? :)
    You would have to install electronic door openers, which ads weight, which would probably cancel any savings. :)
    Don't forget sealing off the grill that catches all that wind.
     
  4. jerrymildred

    jerrymildred Senior Member

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    It would have to help, but the change would be so small I don't think you could tell the difference.

    Interestingly, Mythbusters once tried putting a dimpled surface on a car like a golf ball. They covered the car with clay and then cut out the dimples from the clay. Compared to the car with clay and no dimples (same weight), they saw quite an improvement in mpg at 65 mph. It went from 26.x to 29.x, I think.
     
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  5. Pluggo

    Pluggo Senior Member

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    Just park with a window open, hopefully in a garage.
     
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  6. ASRDogman

    ASRDogman Senior Member

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    That works, until you have to park somewhere else.
    You could trash the car so no one wants to steal it. :)
     
    #6 ASRDogman, Feb 10, 2019
    Last edited: Feb 10, 2019
  7. Mendel Leisk

    Mendel Leisk Senior Member

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  8. padroo

    padroo Senior Member

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    You will save more by keeping the tires properly inflated, not letting the car idle, consolidated trips to the warmest part of the day and avoid starts and stops, keeping the things you don't use in the car because of weight and the list goes on. If you never use your rear wiper it would be no big deal to remove it.

    One more thing, move to Florida where it is summer all the time and avoid those cold NY winters.
     
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  9. Mendel Leisk

    Mendel Leisk Senior Member

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    Gotta say I use the rear wiper about as much as the fog lights, and in the same spirit. Between the need to use it, and the way it swipes maybe 25% (if that) of the rear window glass, pretty useless.

    I could probably recoup more mpg by taking out the near 20 lb jump pack.
     
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  10. JimboPalmer

    JimboPalmer Tsar of all the Rushers

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    [This is a silly wild nice person guess, not based on research]

    I bet you would save more gas leaving the wiper but removing the wiper motor. It is pretty heavy. But neither one will amount to 1 MPG, so you would need very accurate equipment to prove me right or wrong.
     
  11. Grit

    Grit Senior Member

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    You can buy the OBD module that roll windows down when you unlock w/remote. Hop in through the window like bo and luke, then yell "yeeehaaaaw" as you floor it.

    Only block entire lower bottom grill if you have short drives or ICE stays off 70% of the time. The inverter & mg1 temp gets hot to dangerous temps at long hwy speeds, dr prius says so.
     
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  12. Grit

    Grit Senior Member

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    Pull the rear bench seats out also. Soon as I can figure how to get the damn rear bench seats out, I'll do a real world mpg comparison and not post it on here.
     
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  13. Mendel Leisk

    Mendel Leisk Senior Member

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    I've got 100% grill block on lower grill right now. I go from 50% to 100% if and only if ambient temps are staying below freezing, and we're in a cold snap right now. Even so, if I was for example going up Mount Seymour, I'd STILL take it all out, regardless of ambient temp. From freezing to +10C I do just 50% lower grill block, and above 10 it all comes out.

    Inverter rad is behind upper grill on third gen, lower grill on second gen.
     
  14. orenji

    orenji Senior Member

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    There are wiper delete kits available. If you look under modifications you will see ones that have been done.
     
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  15. James Powers

    James Powers Senior Member

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    I removed mine. My reason wasn't about aerodynamics though. Mine was for looks. I literally never used mine but could see it out of my rear view which I hated... I did not see a gain in mileage.. At this point, unless you are trying to accomplish land speed records, it wont make a difference other than look better without it.
     
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  16. padroo

    padroo Senior Member

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    I have heard of people removing their front wipers because it looks better without it.

    The ones I am talking about live in very dry parts of the country and these cars are not daily drivers.
     
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  17. Mendel Leisk

    Mendel Leisk Senior Member

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    I heard in Russia there's a phenomena: it'll start to rain, and all the cars pull over, to install their wipers. They're a hot theft item, like the CAT's in London.
     
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  18. James Powers

    James Powers Senior Member

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    Ive seen a few guys delete just one front but not both, thats just crazy lol
     
  19. Grit

    Grit Senior Member

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    I once saw a pirate driving a prius.
     
  20. ALS

    ALS Active Member

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    The amount of fuel mileage you'll gain will be minimal removing the wiper. You'd gain far more with a grill block or pie plates over the wheels.