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Finally gave up on the "hyper pressures"

Discussion in 'Gen 3 Prius Fuel Economy' started by Jonny Zero, Feb 3, 2013.

  1. Jonny Zero

    Jonny Zero Giggidy

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    For a while, I was running tire pressures in the high 40s, to get the best MPG. But the ride had been too harsh on the 17" Toyo tires. On some bumpy back roads at night, I felt like the headlights were going to get shook off the car, from watching the LED beam cut off shaking to the bumps. All the interior rattling was getting annoying too.

    So I gave up. I settled on 39F/38R. Seems to be comfortable, and quiet. I might experiment with higher pressures when I get new, and different tires, but for the time being, +6 PSI is all I am good for. :(
     
    #1 Jonny Zero, Feb 3, 2013
  2. bisco

    bisco cookie crumbler

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    that's where i run mine, but i don't have 17's. it's a nice compromise between mpg's and comfort.
     
    #2 bisco, Feb 3, 2013
  3. xs650

    xs650 Senior Member

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    The good news is the first 5 psi get you the biggest improvement of any 5 psi
     
    #3 xs650, Feb 3, 2013
    F8L likes this.
  4. bisco

    bisco cookie crumbler

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    that's interesting, i wonder why?
     
    #4 bisco, Feb 3, 2013
  5. Mendel Leisk

    Mendel Leisk Senior Member

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    Our OEM's are 215/45R17. I settled on 38/36 (front/rear), with the low profiles. I do set our winter 195/65R15's a fair bit higher.
     
    #5 Mendel Leisk, Feb 3, 2013
  6. jhinsc

    jhinsc Senior Member

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    On my 15''s I settled on 39/36. Best compromise for ride, mpg, and tire wear.
     
    #6 jhinsc, Feb 3, 2013
  7. iClaudius

    iClaudius Active Member

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    I go with recommended pressures. Better for the tires, much safer, better ride. Car is rated for 50 mpg with the recommended pressures. I put the "riding on rocks" up there with using lap blankets and gloves vs. the heat or sticking the head out the window vs. turning on the AC when it's 100...a mpg too far.
     
    #7 iClaudius, Feb 5, 2013
  8. jhinsc

    jhinsc Senior Member

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    Agree with most - but I use increased pressures mainly to get better tire wear.
     
    #8 jhinsc, Feb 5, 2013
  9. F8L

    F8L Protecting Habitat & AG Lands

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    The mpg gain from increased tire pressure is largest for the first few extra psi. After that the effect provides diminishing returns and the cons start stacking up. I find that between 38psi and 46psi provides the most gains while reducing the negatives. Obviously the exact number will depend on the driver's comfort level, the surfaces they drive on, the outside temps/weather, the speed the regularly drive, the exact tires used, etc..
     
    #9 F8L, Feb 7, 2013
    peterjmc likes this.
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