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Mythbusters - Driving with windows down vs. windows up and A/C on....

Discussion in 'Gen 2 Prius Fuel Economy' started by Jimbo69ny, Mar 18, 2012.

  1. Jimbo69ny

    Jimbo69ny Active Member

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    They found that it is better to drive with the windows up and the A/C on. Is this still the case with the Prius? I was wondering if the difference would be any larger or smaller in our car.
     
  2. F8L

    F8L Protecting Habitat & AG Lands

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  3. cnschult

    cnschult Active Member

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    i saw this episode years ago as i watched this show a lot (Kari Bynum is hot!!!)
    some problems with this experiment:
    1. A/C was on full blast freezing (driver wore a winter jacket), they should have done one with A/C on a more reasonable comfortable setting, not full blast, the gen III prius even has an eco A/C mode which consumes even less energy than our gen II a/c.
    2. they used 55mph which I rarely drive, they should have done one run at 35mph for city driving and one at 70mpg for highway driving.

    I find 20-25% of mythbuster experiments aren't well thought out for all contingencies, this was one of those experiments. Most priuschaters agree that it is better to drive with windows down in the city and windows up in the highway.

    The conclusion about drag is definitely correct, especially above 40mph, but I would have loved to see them use a 4Runner or other SUV that can open the rear window to see if that would cut the drag down as the cabin would no longer be a 'wind socket'. A lot of minivans have rear windows that open outward to allow air to enter and exit the car streamlined without much drag as well.
     
  4. Teddy76

    Teddy76 Junior Member

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    Also, window down is not always all the way. And all the windows. There are different grades. I think it's safe to say in general that open windows to whatever needed degree in city traffic and a/c at highway speeds gain the highest mpg.
     
  5. wick1ert

    wick1ert Senior Member

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    Kari Byron ;) and I would agree with that sentiment bout her lol.

    I had a Nissan Maxima at one time, and I did a drive from here to FL. I netted the same MPG doing 80 MPH with the A/C on and off. The biggest difference, was that I could still hear with the A/C running.

    As was said earlier, the biggest hit is when the A/C is running full speed to cool the interior temperature down. Once that happens, I've noticed minimal difference in MPG whether around town or not.
     
  6. F8L

    F8L Protecting Habitat & AG Lands

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    *drools* Kari.......
     
  7. F8L

    F8L Protecting Habitat & AG Lands

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    One way to mitigate the losses due to having windows down or the AC, at highway speeds, is simply crack the driver's side window about 4" or so and crack the rear passenger side window about the same. This will create airflow through the car and in most cases is enough to cool the cabin down to ambient temps. I don't mind 90deg temps so this works fine for me. :) This technique also eliminates the low frequency but highly annoying sounds/feeling that usually occurs when you roll down only one window.
     
  8. cnschult

    cnschult Active Member

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    I knew its Byron, I just went to a Lakers game, that's why I had Bynum on my mind. Both are enjoyable to watch, but for completely different reasons.;)
    bynum.jpg
    kariBYRON.jpg
     
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  9. NinnJinn

    NinnJinn Member

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    I haven't hit sweltering heat with high humidity yet. However on a recent trip the temp was 85 out and I got tired of listening to the wind and it was starting to get quite annoying running 65-70. so I kicked on the A/C.. I could not hit above 45mpg in the cities to save my life! The ICE ran constantly... So what I ended up doing was 50+ mph Windows up A/C on, in city or speed limit under 50mph I would kill the A/C and roll all 4 windows down..
     
  10. cproaudio

    cproaudio Speedlock Overrider

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    Where's Byron? The red head in front of you?
    [​IMG]
     
  11. uart

    uart Senior Member

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    LOL, that would be creepy right. Stalking her at the basketball and taking photos of the back of her head. :eek:

    Funny that was the first thing I thought when I looked at the pic too. :D But no, he's just showing a pic of a Lakers game to point out how he confused Byron with Bynum. [ame=http://en.wikipedia.org/wiki/Andrew_Bynum]Andrew Bynum - Wikipedia, the free encyclopedia[/ame]
     
  12. DavieDanie630

    DavieDanie630 New Member

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    This would definitely be an interesting experiment. I personally, drive with the windows down only from speeds between 15-45mph. Any speed over 45mpg, the wind becomes to deafening and uncomfortable no matter what I'm driving in, and I prefer to use all my senses while driving.
     
  13. cnschult

    cnschult Active Member

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    no, i wasn't just showing a picture of the game, #17 is Andrew Bynum in the center of the photo, my camera phone is garbage but all you SoCal Laker fans should be able to make out #24 Kobe as well.
    Tonight I'm going back to watch Dwyane & LeBron, if I just wanted to prove I was there I would have used this picture for your entertainment: ;)
    cheerleaders.jpg