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Improved MPG by removing seat

Discussion in 'Gen 2 Prius Fuel Economy' started by zenMachine, Jul 25, 2007.

  1. JimboK

    JimboK One owner, low mileage

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    To nudge this back on topic ....

    I don't know how much the seat weighs, but let's give it a generous 200 pounds. Using the MPG Mileage Simulator, a decrease in weight by that amount would gain 0.9 MPG at 55 MPH. This assumes the following:
    • Steady speed
    • Level terrain
    • 80F air temp
    • No winds
    • Goodyear Integritys inflated to 44/42
    • Weight of occupants and cargo: 300#
    • Climate control in use with temp set on 76
    I agree with the others who say something else has to be at work here. First thing I would suspect is winds. It's less obvious and has a greater impact with small changes than most of the other variables. A 5 MPH tail wind adds 4.9 MPG. A 5 MPH head wind drops it by 4.6 MPG. A wind coming from 45 degrees off the front is even worse, dropping it 5.2 MPG.
     
  2. darelldd

    darelldd Prius is our Gas Guzzler

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    <div class='quotetop'>QUOTE(JimboK @ Jul 25 2007, 06:17 PM) [snapback]485142[/snapback]</div>
    Yahoo, that's a heavy seat! I've had mine out several times and can guarantee that they aren't anywhere near that! If mine weighed that much, I probably WOULD replace them with something lighter and more comfortable. I'd say the 60 pound guess is quite a bit closer... and of course that makes the answer even less impressive here...

    Now, taking the plastic wheel covers off. That's got to be good for at least eight mpg! Oop, sorry. We were trying to get BACK on topid. Bad Darell.
     
  3. JimboK

    JimboK One owner, low mileage

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    <div class='quotetop'>QUOTE(darelldd @ Jul 25 2007, 10:21 PM) [snapback]485201[/snapback]</div>
    And that was part of the point. Like I said, it was generous. Admittedly, very generous. :)
     
  4. zenMachine

    zenMachine Just another Onionhead

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    Thanks for all the healthy skepticism. It'll probably take me a few tanks to comfirm this theory. I'm hoping to be able to keep the seat out a while longer, as long as the wife doesn't complain. I think she kinda enjoys sitting in the back with all that leg room. And of course the baby loves having momma back there too! :)

    Speaking of the wife, she had the car the whole day yesterday and today I noticed the MPG has dropped down to 50. Anyone else had this happen to them?
     
  5. JimboK

    JimboK One owner, low mileage

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    <div class='quotetop'>QUOTE(zenMachine @ Jul 26 2007, 11:16 AM) [snapback]485419[/snapback]</div>
    Does she weigh more than you? :D

    Sorry, couldn't resist. ;)
     
  6. likesmpg

    likesmpg Junior Member

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    I have taken out the big trunk floor mat, cargo cover, and hooks & tie-down attachment kit for the spare tire. When I go to the store, etc. I'll put in the mat and cover but on a daily basis I leave them out. Every ounce counts. Come to think of it I should take out the rear seat floor mats also since 99.9% of the time there are 2 or less people in the car. I have debated and used to drive without a spare tire when I lived 5 miles from work, but now I am 15 miles and I know the day I take it out is the day I'll get a flat, so it goes with me. Not very heavy anyway...
     
  7. fairclge

    fairclge Member

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    <div class='quotetop'>QUOTE(JimN @ Jul 25 2007, 08:28 PM) [snapback]485119[/snapback]</div>
    I agree with all of that…
    I’ve read about the 4 + power stages with the Prius. I did not know the full effect that after the initial ICE warm up, the Prius is still effected by coolant temperatures and not at max operating coolant temperature.
    So bottom line does the block heater help to move the Prius quicker through the stages allowing more battery only use and an overall increase in MPG.
    You guys check my line of thinking and about temps and does the EBH use in summer/winter improve milage.
     
  8. zenMachine

    zenMachine Just another Onionhead

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    <div class='quotetop'>QUOTE(JimboK @ Jul 26 2007, 10:26 AM) [snapback]485427[/snapback]</div>
    Actually, she's only 2/3 my weight. So there goes my theory!!! :)
     
  9. JSH

    JSH Senior Member

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    <div class='quotetop'>QUOTE(likesmpg @ Jul 26 2007, 10:29 AM) [snapback]485429[/snapback]</div>
    I've thought about taking the spares out of my cars too. I've been driving for 12 years and have never had a flat tire. All that time I've been dragging around a spare tire, jack, and tire iron. (The VW has a full size spare) I've thought about just leaving out the spare and getting a plug kit like I have for my motorcycle. That and we have two cars so my wife could always bring me the spare if I wanted it or use the insurance free tow that we have and have never used.
     
  10. berylrb

    berylrb Member

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    <div class='quotetop'>QUOTE(JimboK @ Jul 25 2007, 09:51 PM) [snapback]485216[/snapback]</div>
    Exactly, that's why I suggested way back at post #2 or 3 that possibly the AC was contributing to cooling the battery, thus reducing load on the engine, thus better gas mileage, admittedly that might be far-fetched, but I was and still am quite sure that if the seat did contribute it contributed by reducing the load on the engine through some variable other than weight reduction.

    But alas, like many have posted many takes will really tell, might just be a lot of tailwinds on that tank. :p
     
  11. sje333

    sje333 New Member

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    <div class='quotetop'>QUOTE(zenMachine @ Jul 26 2007, 10:16 AM) [snapback]485419[/snapback]</div>
    Your wife needs a lesson in driving to maximize fuel economy. Driving technique has a lot to do with fuel economy. Nothing frustrates a Prius owner more than getting in and beating their fuel economy. Every time I drive my mother's Prius I edge the tank statistics up. I think she accelerates too slowly, but I'm not sure. I also drove part of a road trip with a friend who had been getting about 38 mpg at 75 mph with some strong crosswinds. I averaged 42 on my leg of the trip in almost identical conditions just by holding the accelerator steady. She had been incessantly adjusting the accelerator...and not in a pulse-and-glide way.
     
  12. Rae Vynn

    Rae Vynn Artist In Residence

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    I have a carpool buddy, who is now riding with me twice a week.
    He weighs, I estimate, about 250 lbs.

    The MFD does not register much difference on the days he is with me, to the days that he isn't. Not enough to factor in. The week he was on vacation, my MPG wasn't any different, by calculation.

    I would look at other factors, really.
     
  13. Flying White Dutchman

    Flying White Dutchman Senior Member

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    bump

    i dont think the car site made the TP first post geth better mpg

    i thnk the removal of the car amp including the car seat dit it!

    When i drive my prius with nav and donw use the nav i sometimes stil hear the DVD onder my seat doing something

    so nav on standby, voice system on standby and amp on standby...
    i am thinking about making a switch to shut it off!
     
  14. 9G-man

    9G-man Senior Member

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    I have plans of doing a similar experiement for a tank or 2, when it gets a little warmer.
    There is no doubt that excess weight reduces gas mileage. I can immediately tell a difference in my Prius with even just one passenger. I cannot achieve or maintain electric only modes (stealth) to as high of speed or durations, cannot sustain glides at reasonable speed for as long either.
    Furthermore, I see greater rises in average mileage during the latter half of a tank of fuel, presumable because the car is lighter then too.

    What I'm gonna do it remove the passenger seat, rear seat and maybe the spare tire. Just for kicks, and then do my routine drive for a tank.
    I think the results will be surprising.
     
  15. abq sfr

    abq sfr New Member

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    Spare tire could be considered a safety item... Back in 1957 in our Buick Roadmaster my daddy was stopped at a stop sign, I was asleep on the back seat, and we were rear-ended by a drunk going around 60. I had no injuries, cops said the spare tire in the trunk probably saved my life. Might want to take the spare out for only a short time.
     
  16. 08Prius

    08Prius New Member

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    I have an 08 and after reading all of you guys comments about how to improve MPG, I did Improved from 56.1 MPG to 58.7 MPG in city without using AC base on 31 MPH and 50 MPG to 52.5 MPG base on 65 MPH with AC. I've tried everything to improve my MPG. Below is what i have done :
    1. Fill gas half of a tank to reduce heavy weight on a car
    2. Set temp to 73
    3. Tire Pressure 45 PSI
    4. Slowly step on gas penal
    5. Accelerate to 36 MPH on 40 MPH (IN CITY ONLY)
    6. Release gas penal all the way for only 2 second and slowly step on gas penal to keep your speed on 31 MPH.
    7. Shut off AC
    8. Release gas penal if you see a stop light in RED Color ( This will always save you a lot of gas everytime you do it)

    WHY YOU HAVE TO REMOVE YOUR SEAT IF YOU CAN GET ALMOST THE SAME MPG?

    HOPE TO GET MORE IDEA TO IMPROVE MPG !!! PLEASE LET ME KNOW HOW MANY MPG DO YOU MOST GET?

    THANK YOU EVERYONE !!!:)
     
  17. ZC1

    ZC1 Junior Prius Owner

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    You can actually gain mpg by removing the seat?? No, really?

    HOT DOG! then I'm gonna get the best gas mileage ever!

    First go the back seats (that's with an "S")
    Then the spare tire and that plastic tool storage thingy-a-bob
    Don't need all this extra carpet back here either
    Then for more mpg, remove the headliner, passenger seat (nobody rides there any way), part of the front dash, the stereo I can toss out too.
    I figure I can drive sitting on a 3 legged stool too, so no problems there.

    Wow, my wife is gonna be excited.

    "But honey..., look at all this new found gas mileage, we're saving money by the wheelbarrow"
    "Hello 911?"

    ZC1
     
  18. Rascal

    Rascal New Member

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    Ok...now I am worried;) When your talking about increasing gas mialage by taking out the seats it's a bit over the top. Whats next....take out the carpet? How about the knobs on the radio? Waite....lets just all walk!