Pulse / Glide

[jimsoh]

I read pulse / glide (but in my mind I hear accelerate / coast), which sounds mighty boring, and aggrivating to those around you, if not downright dangerous.

After driving my Prius for a few months, readng & learning here, and experimenting, I've come to a better understanding, and I think I see now what I had been mising.

Mainly that pulse / glide is more of an inertia managment system, and not just an accelerate / coast situation.

My first tank after buying the Scangauge is going to be at or near 60 mpg (MFD) and if it weren't for a 120 mile interstate trip into the teeth of a 20 mph headwind, it may have been closer to 63 mpg.

As an after-thought, are there others who see that better fuel economy is easiest to achieve, when you stay under 38 or between 45 & 55 mph.

Keep up the good work, and all the good info flowing.

[Alolio]

I have found that if I keep my cruise control between 50 and 55mph on the freeway, on longer trips I'll get 55-65mpg. The drive between Seattle and Tacoma comes to mind - about 90 miles round trip for me. On that run, I typically get 63mpg with cruise control alone. I'll also get flicked off and cursed at a number of times...

Staying under 38 alone isn't enough to maximize fuel economy on shorter trips. In my experience, moderating acceleration, using hills, pulse/glide, etc, are all keys to the short haul. Driving the Prius like I'd drive a conventional car, I'll get 45 around town. Driving it more like a Prius, I'll get closer to 50.

[diamondlarry]

I stayed below 40 as much as possible last month and finished off a tank this past Saturday that I started on 7/6/08. It lasted 1143.0 miles and it averaged 92.2 mpg.

[sandman]

Show-off

I don't know how you guys get that good MPG and so many miles.. I can almost hit 60MPG..Congratulations

[diamondlarry]

The MFD is usually optimistic and I found that the odometer under-reports by 1.6%.

[bac]

Originally Posted by diamondlarry

First of all - WIPE THAT SCREEN OFF!

Secondly, quit showing off.

... Brad

[9G-man]

Originally Posted by jimsoh

I read pulse / glide (but in my mind I hear accelerate / coast), which sounds mighty boring, and aggrivating to those around you, if not downright dangerous.

After driving my Prius for a few months, readng & learning here, and experimenting, I've come to a better understanding, and I think I see now what I had been mising.

Mainly that pulse / glide is more of an inertia managment system, and not just an accelerate / coast situation.

My first tank after buying the Scangauge is going to be at or near 60 mpg (MFD) and if it weren't for a 120 mile interstate trip into the teeth of a 20 mph headwind, it may have been closer to 63 mpg.

As an after-thought, are there others who see that better fuel economy is easiest to achieve, when you stay under 38 or between 45 & 55 mph.

Keep up the good work, and all the good info flowing.

If you're going to have a 60 MPG tank, then you're doing something right, and congrats.
But some of the the things you say could be mis-understood by a new Prius driver.
First, the P&G technique can be applied at any speed, for any combination of duration and it's not boring, aggrivating nor dangerous if done sensible.
P&G is really a method to get the Prius gas engine (ICE) to shut down and stay shut down, for as long as possible. Knowing how to do it is important, and when to do it even more so.
And the sooner owners realize their car is capable of moving, and using no gas, the better they will try to maximize the time it spends doing just that.
Second, the word "coast" just can't be used with the Prius to communicate anything. Coasting in a regular car simply means taking ones foot off the gas, and it's the only other alternative to having ones foot on the gas.
In a Prius there are several forms of "coasting". And all of them are ways of traveling with no gas consumption.

Those forms of "coasting" I speak of are Regen, Glide, and Stealth.
Simply taking you foot off the gas allow the ICE to shut down and starts Regen (which is good), but unles you need to slow or stop it's drag is inefficient.
Having taken your foot off the accelerator and then then lightly reappling pressure on the accelerator,
you will start a glide (no arrows). This is really the highest form of travel efficientcy in Prius. Apply a little more pressure and electric power is initiated and that's a good, gas free, way to travel too, up to a point.

Third, the whole idea of staying below 42MPH, or driving "slow", is not to just poke along at slow speed, but rather, being below 42MPH allows full exploitation of the Glide and Stealth capabilitys, differently than can be done above 42.
A knowlegable Prius owner need to know what it can do, and when.

P&G is a Prius manipulation technique. Enertia management is simply efficient travel, in any craft. But they do go hand in hand.

A pulse is really anything that initates acceleration, and a glide (regen or stealth) any ICE off mode that maintains forward motion without the use of gas. Maximizing the latter is what the Prius is all about.

[jimsoh]

9G-man, Thank you for that needed 2nd level of explanation. Being fairly new I sometimes forget others may be newer than me. Kudos.

[KK6PD]

Originally Posted by jimsoh

.

After driving my Prius for a few months, readng & learning here, and experimenting, I've come to a better understanding.

Mainly that pulse / glide is more of an inertia managment system, and not just an accelerate / coast situation.

Keep up the good work, and all the good info flowing.

Well, here is a lad that get's it!!!!
I could not have said it better myself!!!

I used to go to the Reno Air Races for many years, and one of the attractions was a gentleman named R.A. "Bob" Hoover. He would to demo flights with a P-38 Lightning and another type of twin engine aircraft. The whole point of these flights was to demonstrate "Energy Management" as it applied to flight. He woulod get to a certain altitude and proceed to shut off the engines. He would then spend the next 20/30 minutes just gliding. building up speed in a dive, and using that speed to climb back to altitude, while doing twists & turns. I watched that routine many many times, after all we went 20 years in a row!!. He was VERY GOOD!!!

The day I got my Prius, on my first drive, all I could think about was Mr Hoover, the Energy Management Series, and applying those techniques to driving. No not climbing and diving, but the use of inertia, brakes, and accelerator!!! Now 3500 miles later, driving through the foothills of Los Angeles, my first tank was a pitiful 41MPG. But I learned to "Fly" the car, and its paying off!!! I am now getting 47+ MPG.

It has actually been a very enjoyable learning curve!!

73 de Pat KK6PD

[richard schumacher]

Inertia or energy management is a nice way to describe it.

Summarizing: to maximize fuel economy
- Don't floor the gas pedal, but do accelerate briskly (the engine is most efficient under substantial load)
- Gliding (no arrows) is better than coasting,
- Coasting is better than braking,
- Braking is better than stopping.
- Don't use "B" (it's there only to avoid riding the brakes on long downgrades).