1. Attachments are working again! Check out this thread for more details and to report any other bugs.

Pulse and the Elusive 'Glide' ???????

Discussion in 'Gen 3 Prius Main Forum' started by revhigh, Jan 25, 2011.

  1. revhigh

    revhigh MPG Enthusiast

    Joined:
    Jan 2, 2011
    986
    141
    0
    Location:
    PA - Pocono Mountain Area
    Vehicle:
    2010 Prius
    Model:
    II
    Thank you Kgall. I'm going to add gallons per hour to my scan guage 4 guages in order to be able to tell warp stealth on the highway. At highway speeds the ICE is always turning I guess, so the only way to tell is to look at GPH ... if that is zero, I guess you're in warp stealth mode, right ?

    REV
     
  2. fuzzy1

    fuzzy1 Senior Member

    Joined:
    Feb 26, 2009
    17,115
    10,044
    90
    Location:
    Western Washington
    Vehicle:
    Other Hybrid
    Model:
    N/A
    Over at CleanMPG, Super Highway Mode is different than Warp Stealth, and is a gas burning mode. It is typically found at a narrow span of throttle position and ignition advance that produces very efficient sustained operation. Unfortunately the power level limits speed to lower than most drivers want on the highway, at least at today's cheap gas prices.

    SHM can work well on the Gen2 Prius (New Prius - "Super Highway Mode" Technique (SHM)), and the Civic Hybrid has a very similar mode. Gen3 doesn't do this as well ( 2010 Prius-III P&G, SHM and WS ... ).

    Even my Subaru seems to have a similar mode, though at much lower MPG. I can't get this mode on level roads at 60 mph without a good tailwind, but can achieve it under more conditions in the mid-50s. When $4+ gas coincided with such weather, I coaxed the Suby across the state (325 miles) at almost 39 mpg.
     
    1 person likes this.
  3. kgall

    kgall Active Member

    Joined:
    May 3, 2009
    984
    152
    2
    Location:
    Olympic Peninsula, WA
    Vehicle:
    Other Hybrid
    Model:
    N/A
    You're welcome.
    You've probably seen the more accurate definition someone else gave of Super-highway mode.
    Anyway, I don't use a scangauge. I assume that my ICE is not burning fuel when the instantaneous MPG bar (shown on the right of the MPH number) goes up to 100, no matter what my speed.
    That's correct, isn't it, gang??
     
  4. fuzzy1

    fuzzy1 Senior Member

    Joined:
    Feb 26, 2009
    17,115
    10,044
    90
    Location:
    Western Washington
    Vehicle:
    Other Hybrid
    Model:
    N/A
    No, it isn't. When I had ScanGauge showing iMPG, there were numerous times it displayed numbers in the 100-200 range, but still burning gas. A small offset error in gallons-per-hour often caused it to show non-finite MPG when no fuel was being burned, but my memory is of that happening only with displayed MPGs of 350 and higher.

    But I rarely have this particular gauge displayed.
     
    1 person likes this.
  5. revhigh

    revhigh MPG Enthusiast

    Joined:
    Jan 2, 2011
    986
    141
    0
    Location:
    PA - Pocono Mountain Area
    Vehicle:
    2010 Prius
    Model:
    II
    I'm replying to my own statements LOL !!

    I've found, upon further experience and study, that my statement regarding 41 MPH kick on / kick off of the ICE was incorrect. It is in fact right at 45 MPH as everybody says the GEN III's are. I don't know what changed ... maybe my car wasn't completely warmed up, or I passed through that speed at too high of a delta, and by the time I looked it was lower/higher than reality.

    Either way, my car does in fact start/stop the ICE right at 45 MPH as everyone else reports.

    I love this car ... my 'from brand new' mileage in absolutely horrible winter weather has averaged 45.7 as the fuelly below shows. This is making me quite hopeful for 55-60+ MPG when the nicer weather rolls in. A big help for me is having my ScanGuage II. I love it when I've just driven 2 or 3 miles and the RPM's remain at ZERO with ZERO GPH, and the CONS numbers just keep rising. The Scanguage is essential for understanding the true workings of your hybrid, and will DEFINITELY help you maximize your mileage. If you're technically oriented, and are struggling to get much better than 40MPG, the Scanguage will be invaluable to you.

    REV
     
  6. MrSpokk

    MrSpokk Junior Member

    Joined:
    Mar 26, 2011
    2
    0
    0
    Location:
    Lake Havasu City, AZ
    Vehicle:
    2011 Prius
    Model:
    Two
    I have been playing with trying to get the zero arrows condition and as others have reported, it is nearly impossible on my 2011. Using the ECO screen and enough go pedal to eliminate regen is fairly easy. However, I notice that if I throw the tranny into neutral the car doesn't slow down nearly as much. The scanguage still shows 99.99 mpg. However, the battery seems to go down even though no arrows are showing on the car/motor/engine/wheels display. It seems that mpg would be better in neutral than in 1/8 bar of ECO. I've ready somewhere that using neutral still uses gas but apparently not much. Any comments?
     
  7. ItsNotAboutTheMoney

    ItsNotAboutTheMoney EditProfOptInfoCustomUser Title

    Joined:
    Jul 18, 2009
    2,287
    460
    0
    Location:
    Maine
    Vehicle:
    2010 Prius
    Model:
    II
    Ken@Japan has noted that for the Gen III getting fully engine off gliding isn't as important, so you want to concentrate on keeping it out of regen.

    A gauge that can display the RPM and current, such as the ScanGauge or UltraGauge, would make it easier to control the glide.

    Putting the car in neutral means the car does what it was doing. If the engine was running it idles, if it was engine off it glides.

    However, note that while in neutral:
    a) The traction battery doesn't get charged.
    b) You don't want to be going engine off at very high speeds, for the same protective reasons that the Prius normally spins the engine above 45mph.
     
  8. fattymoocow

    fattymoocow New Member

    Joined:
    Mar 29, 2012
    96
    8
    0
    Location:
    Richmond, VA
    Vehicle:
    2012 Prius
    Model:
    Four
    Sorry for bumping such an old thread but I've learned so much in this thread and I have a question regarding the bolded statement. Why is it so bad to have the engine in regen mode? Like if you were to let your foot off the gas pedal and you see the green regen arrows (I know after reading this thread that I should ignore this screen), does being in regen mode slow down the car slightly so that the car isn't at it's optimal glide?

    And second question related to this same situation, in order to glide and keep it out of regen mode on a Gen III, does this mean you're pressing the gas pedal in that first 1/8 portion of the HSI bar so that I would actually be slightly using the electric motor (if I was using the energy screen with the arrows, I would be referring to when the arrows are yellow). Is this how you keep the car out of regen mode in a Gen III then since it's so extremely difficult to get it to a no arrow zone?
     
  9. fuzzy1

    fuzzy1 Senior Member

    Joined:
    Feb 26, 2009
    17,115
    10,044
    90
    Location:
    Western Washington
    Vehicle:
    Other Hybrid
    Model:
    N/A
    Regen does slow down the car, and more than slightly. Don't forget [ame="http://en.wikipedia.org/wiki/Conservation_of_energy"]conservation of energy[/ame] or the [ame="http://en.wikipedia.org/wiki/First_law_of_thermodynamics"]first law of thermodynamics[/ame]. Energy is not free, and our machines that convert energy between electric and mechanical and chemical forms are less than 100% efficient.
    This is mostly correct, except that the HSI bar disappears when you glide -- nothing lit in the Regen portion of the bar (left ~1/8 of the bar), nothing lit in the thrust portion of the bar (right ~7/8 of the bar). And when gliding, the electric motor is not really being used. It will have no thrust, no drag.