Is it me or is it unbelievably hard to put Prius into "no arrow state" while going above 40 mph. What is other's experience?
First, the technique is called "Pulse" and glide. Next, you're correct, it is very difficult and not something that is considered effective above 40-41mph. That is b/c the HV ECU forces the ICE to spin above 41mph and almost any accelerator input will result in fuel flow to the ICE. Pulse & Glide is most effective b/w about 20-39mph.
Yes, 42 MPH is the official cut off for gliding. I live in a hilly area and can be gliding along ok down a hill, but as soon as I hit 42 the arrows start up from the battery to the wheels. At this point, I'll usually go into Neutral. But only if the hill isn't steep enough to maintain speed and give regen at the same time. As long as you have a good SOC (state of charge) on the battery, you can still increase speed above 42 without gas being consumed by the engine (99MPG), but I believe it will be spinning nonetheless.
<div class='quotetop'>QUOTE(CrazyRussian @ May 15 2006, 11:38 AM) [snapback]255637[/snapback]</div> Both previous responses to your question are true for me too. There is another technnique I first read about here on Priuschat that seems to work well. I keep the MFD on the screen that show the veritical bar graphs and the regeneration icons. The height of the bar on the far right reminds me to take the lead out of my foot and let the Prius "coast". Often that correlates with the electric motor being deployed at speeds higher than 42 MPH. It is just a technique but it helps me visualize better or worse gas burning efficiency. B)
The large bulk of my driving is done at speeds in excess of 42 MPG, mostly multi-lane state highways. When I'm not stopping or accelerating from a dead stop, I'm maintaining speeds above the posted 40 MPH to keep from getting run over or flipped off. For that reason, I get increasingly frustrated when people tell me the sucess they are having with their Pulse-n-Glide techniques at speeds below 40 MPH. GRRRRrrrrrr. But that's not to say that it can't be done. If you are truly looking for high mileage, you must always be aware of your car's propulsion at any given time and press on the gas as little as is required to maintain speeds. Only in the last few miles of my drive is the terrain flat. On that stretch, I can maintain 60 - 80 MPG at 50 - 55 MPH. I just wish it were like that the whole way.
I think the Push and Glide will get you better fuel mileage than the Pulse and Glide but it is hard to push a car above 40mph. All kidding aside I have glided above 50mph before but its very very hard to do. You have to feather the pedal just right. The sweet spot felt like a millimeter or less. You do have to have the engine and battery warmed up and in a certain state to get it to work.
<div class='quotetop'>QUOTE(CrazyRussian @ May 15 2006, 07:38 AM) [snapback]255637[/snapback]</div> I use P&G between 20 and 40 mph, which isnt often, but it saves fuel. Otherwise, I look at the current MPGs and try to maximize them. On the freeway (a good part of my driving, too) I use cruise control as much as possible. So far, best trip has been 58 mpg. Originally, I did try to do the no arrows thing, but I found that for me, it took too much of my attention off the road.
As everyone saying, the Pulse and Glide above 42mph is hard and little benefit for mileage. The best highway driving strategy was discussed among Japanese enthusiast... We know slower is better for mileage, but it is not good idea to drive at 40mph on highway. So, define your target speed, say 60mph, then set CC at that speed on flat road. When you drive uphill, cancel the CC, then maintain your speed 56-58 mph manually. When you drive downhill, maintain your speed 62-64 mph manually. When you return to flat road, resume the CC for 60 mph. Ken@Japan
<div class='quotetop'>QUOTE(ken1784 @ May 16 2006, 08:49 PM) [snapback]256602[/snapback]</div> I just started doing that this weekend. I used to let the CC maintain the speed of the car on uphills and downhills, but it seemed like the ICE was revving very high to maintain speed going uphill. Now, I know the ICE is designed to do that and it is more efficient, but I've been cancelling the CC uphill and letting my speed drop just a bit. The engine is not revving as high and I'm wondering if I will get more MPG. Probably not. I'm probably thinking too much about it, right? But I've been doing what Ken@Japan says above.
<div class='quotetop'>QUOTE(eyeguy13 @ May 16 2006, 07:09 PM) [snapback]256609[/snapback]</div> It works, for most cars actually. I did what Ken@Japan stated today while driving my Dad's big Duramax Diesel dually and averaged 22MPG instead of 16.
<div class='quotetop'>QUOTE(ken1784 @ May 16 2006, 08:49 PM) [snapback]256602[/snapback]</div> So Ken@Japan, Why did you pick +-4 MPH from target? Let's say the target is 73 mph would the uphill then be 69-71 and downhill likewise? hmmm, b
<div class='quotetop'>QUOTE(berylrb @ May 17 2006, 01:16 PM) [snapback]256654[/snapback]</div> We don't have any data at 73mph, it is too fast to test in Japan. The plus/minus 4mph is just an example. You can find your own variance. You are driving your car by your gasoline. Ken@Japan
Oh I see, trial and error! Thanks at first I thought you had some forumula in mind. At times CA driving feels like Daytona racing that's for sure ... b
<div class='quotetop'>QUOTE(berylrb @ May 17 2006, 11:23 PM) [snapback]256846[/snapback]</div> I enjoy driving the zigzag Lombard street in San Francisco. Ken@Japan
Yes, that's buzz, eh? Next time you're in town check out Vermont it's crookeder and steeper, but not as pretty. There was someone in a expedition I believe who was going down Lombard and for some reason got out, I seem to recall to check on damage hitting the brick wall, no parking brake, car started down hill and flipped, sad ... b
I have additional input on this topic, but I think I'm going to fire up another thread for it since I'm looking for serious feedback on something to add to various widely-read knowledge bases. Look for "warp stealth". . _H*
<div class='quotetop'>QUOTE(ken1784 @ May 17 2006, 08:46 AM) [snapback]256878[/snapback]</div> OK Ken you can not drive your Prius on Lombard street and Live in Japan at the same time!! Well unless you are better at renting Prii than I am. I am batting 0 for 4 so far. No one ever has one no matter how far I call ahead!! :angry: So fess up Japan or California. I too have seen Lombard Street but that does not mean I have taken my car down it! I would not like to be a Prius driver in San Francisco. I would bet that it is tough to break 60 driving in town!!!
