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Impreesed FE (58 MPG) from my one-week prius

Discussion in 'Gen 2 Prius Fuel Economy' started by maclion, Mar 4, 2008.

  1. maclion

    maclion Junior Member

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    2008-3-1:

    Milage:218
    Temperature: ~40 F @departure ~70F @arrival
    Route: Between Laramie, WY and Denver, CO (mostly interstate highway)
    Distance is 296 miles
    Altitude difference: over 1000 meters
    Car condition: Upper-gill block & partial lower-grill block; 42/40 PSI
    Driving condition: speed is between 60 and 75 MPH.
    MPG (shown on MFD): round trip is 53 MPG, Laramie to Denver (mostly down hill) is 58 MPG.

    I am impressed by this FE considering it still in break-in period. I was trying to use P&G and wrap stealth tech. P&G is easy to achieve when speed is lower than 40 MPH. However it is very hard for me to get wrap stealth (it seems need more sensitive foot). So when the speed is around 70 MPH, I just to hold the pedal position to get the state same as Pulse (see the attached picture).
    iMPG could always get over 70 MPG and even 99.9 MPG.

    My question:
    1)Is this state could be called “steady state�
    2)Does this state is the good for high speed (best load)?
    3)Does ICE shut off when iMPG show 99.9?
     

    Attached Files:

  2. dogfriend

    dogfriend Human - Animal Hybrid

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    Location:
    Carmichael, CA
    Vehicle:
    2007 Prius
    1. I think some people are now calling this Super Highway mode. Hobbit has a very good explanation of Warp Stealth and why is can sometimes be hard to obtain. It depends upon Battery SOC.

    http://techno-fandom.org/~hobbit/cars/warpstealth.html

    2. Whatever works best for you. I think that there is a general consensus that staying below 65 mph is best for FE.

    3. If you have a Scangauge or other method to monitor RPM and fuel use (GPH), you can see that 99.9 iMPG does not necessarily mean the engine is off. You can still have light fuel use at 99.9 mpg.
     
  3. maclion

    maclion Junior Member

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  4. dogfriend

    dogfriend Human - Animal Hybrid

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    Location:
    Carmichael, CA
    Vehicle:
    2007 Prius
    I don't think there is any harm to the engine in any event. The HV ECU is actually what determines the throttle opening, even though it seems like you control it with your right foot.

    What really happens is that you signal how fast you want to accelerate, then the HV ECU determines the most efficient way of accomplishing it. But the HV ECU can't determine upcoming terrain changes or if there is a red light ahead - this is where the driver can improve the FE by making savvy decisions.

    I'm still in the learning mode with mine after a year, but getting better FE at the same time this year compared with a year ago.