Pulse and Glide question

Discussion in 'Honda Hybrids' started by DanaLinder, Jun 2, 2010.

  1. DanaLinder

    DanaLinder Member

    The glide portion of my Pulse and Glide is tremendously shortened by regen.
    I'm happy with the regen when the battery is low, but once it's up to power, I don't care.

    My question is, if I drop into neutral, then put it back in drive when I want to accelerate, am I causing any major wear on the transmission? It just seems like popping it into gear at 50 could be a huge strain on it.
     
  2. Right Lane Cruiser

    Right Lane Cruiser Penguin of Notagascar

    Are you not able to do a "soft glide" with no assist or regen bars and the engine shut down?

    As N back and forth with drive just remember that the CVT is controlled by a computer and don't get on the pedal immediately after engaging drive. Let it find the right ratio (couple of seconds or so), then ease into the pedal.
     
  3. Dream'R

    Dream'R Well-Known Member

    Perhaps you are not getting the glide technique quite right.

    One of the key design features of the HCHII motor is its ability to shut down both intake and exhaust valves when coasting to maximize the regenerative momentum available to recharge the battery pack. However, this is not always desirable when you see an opportunity to use that momentum to extend your glide instead. In order to eliminate the car's natural tendency to regenerate, you need to apply very gentle pressure to the gas pedal so the green bars are just eliminated. Too much and the engine will "refire" and start using some fuel.

    If you want, you can then apply just a tiny bit more pressure until you see a few assist bars showing, if you want to continue in EV mode. (I find it difficult to get any more than 3 or 4 bars of assist before the engine starts up). Learning how to modulate the gas pedal while the engine is "free wheeling" allows you to control the level of regeneration or assist and is a part of learning how to get the most out of the HCHII.

    Perhaps, for practice, you might try putting the display on the metric setting because the fuel consumption display shows how much fuel is actually being used. One bar means no fuel is being used and the engine is simply spinning with all valves closed. Once you have a better feel for how this works then go back to the mpg/mph setting that you will normally want to use. (This is one slight benefit we in Canada have from the metric system when driving the HCHII).

    It's too bad the Honda doesn't give more directions on how to exploite the full potential of their IMA system. I find the driving experience much more engaging when I'm trying to get the most out of the engineering Honda has put into these cars.

    Good luck,

    Roger
     
  4. msantos

    msantos Eco Accelerometrist

    Exactly what Roger said !!! :thumbs_up:


    I'll also add a few more points:

    While you can get pretty good numbers with a properly executed Pulse-and-glide routine, it is still not a technique many folks will resort to for maximum FE. There are a lot of reasons for this so let me touch on a small set:
    1. Unless your foot is well trained, nailing a perfect glide is a bit difficult because even when no regen or assist bars are shown and the fuel delivery is OFF, the car could be regening or assisting at less than one bar. No matter how small, a Regen is drag and an assist is too big an energy leak.
    2. In order to a pulse and glide to be sustainable you must avoid the use of electric assist. This means that P&G must be evoked strategically taking into account the rate of acceleration for the pulse and the potential glide distance ahead. Yes, it can be done but you have to know the roads and topography quite well. An S pulse routine is often preferable.
    3. Even while avoiding assist, the system will bleed energy from the pack while in a glide mode. Placing the transmission in N does not work because that triggers the ICE back on. Turning off the ICE while in N works but that too is not sustainable since your 12V battery and fuel consumption for the first 10 seconds after powerup will suffer.
    4. When driven in a steady state, the HCH-II is perhaps the best car available in any show room in North America. All you need is to be a good/safe driver and develop a steady foot then select a target speed 25-60MPH to let your car take you to ultimate FE bliss.
    5. Unlike other high FE hybrids on the market, the HCH-II engine delivers the widest power delivery spectrum that is controlled by the driver's foot. Other hybrids will benefit from the P&G a lot more because their engines are either ON or OFF and unlike the HCH-II, they are not able to operate on that "run on fumes mode" to the same extent the HCH-II is while operating under its low cam mode.
    Cheers;

    MSantos
     
  5. DanaLinder

    DanaLinder Member

    My apologies and appreciation.

    There is SO much to learn about this car and ways to drive it.

    I briefly looked at pulse and glide. Enough to know what it meant, but no detail on it.

    I will look in more detail before I post again.

    "Keeping your foot on the gas". Who'd of though of that in order to coast? (Actually, someone who read the articles. :) )

    Thanks again,

    Dana
     
  6. Right Lane Cruiser

    Right Lane Cruiser Penguin of Notagascar

    No trouble at all, Dana. We like to help and it wasn't an obvious detail for someone new to the HCH. :)
     
  7. Kacey Green

    Kacey Green Well-Known Member

    Steady state has returned the largest non-competition numbers for me, P&G the lowest other than not hypermiling, though there are times when that works best for me (like a recal in a traffic jam)
     

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