optimum speed for optimum mileage?????
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Yup, pulse & glide is the _maximum_ MPG technique. With about a 20 MPH average speed. Do it anywhere except on a deserted stretch of road and expect to get run over. :shock:
IMO only a proof of concept technique.
[edit typo oops in response to Willies post below. 1 letter in the alphabet & keyboard position different :!:
Thanks Willie :!: ]
IMO only a proof of concept technique.
[edit typo oops in response to Willies post below. 1 letter in the alphabet & keyboard position different :!:
Thanks Willie :!: ]
20 MPG average speed ? Is that in reality OVER 100 MPH? :?
Willie
Willie
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What's pulse and glide?Dougie said:
The technique I use is to just hold my foot steady, and watch the Instant MPG Bar to hold it above 100mpg as much as possible. 45-50 mph seems to be the sweet spot (any slower and the engine lacks enough torque to keep the car rolling).
Hi Electric; pulse & glide is just as it sounds --- power, then coast.
For example, last September 6 of us guys used the technique to set a world's record (farthest distant on a tank of gas) We averaged about 165 mpg over 2300 miles. Some segments were about 180 mpg.
We would carefully accelerate to about 29 or 30 mph, then shut the engine off and coast to about 11 mph, then repeat. Managing the IMA was critical, as to avoid depleting the battery and getting a recalibration.
Insightful Trekker is exactly correct----this method is not practical, but just a proof of concept to show what is actually possible.......
For example, last September 6 of us guys used the technique to set a world's record (farthest distant on a tank of gas) We averaged about 165 mpg over 2300 miles. Some segments were about 180 mpg.
We would carefully accelerate to about 29 or 30 mph, then shut the engine off and coast to about 11 mph, then repeat. Managing the IMA was critical, as to avoid depleting the battery and getting a recalibration.
Insightful Trekker is exactly correct----this method is not practical, but just a proof of concept to show what is actually possible.......
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And your beginning to read like him too :!:
More accurately, you push = infinite MPG. I'd doubt many people have more than a few hundred lifetime miles in them. But your MPG of "coolant" and caloric consumption will skyrocket :!:
More accurately, you push = infinite MPG. I'd doubt many people have more than a few hundred lifetime miles in them. But your MPG of "coolant" and caloric consumption will skyrocket :!:
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IMHO
The slower you go, the better the mpg basically. This holds good down to about 35mph, when the engine starts getting so feeble in lean burn that it can't drive you along.
In my MT I drive at 35-55mph in lean burn as much as possible, gives UK LMPG of 90mpg.
Below about 40mph on A roads or 50mph on dual carrigeways/motorways in UK you become too much of a hindrance to other road users, and are liable to be involved in an accident. Usually due to impatience in overtaking. You would never get away with pulse and glide here for more than a few miles on a deserted country road at 3am
Peter
The slower you go, the better the mpg basically. This holds good down to about 35mph, when the engine starts getting so feeble in lean burn that it can't drive you along.
In my MT I drive at 35-55mph in lean burn as much as possible, gives UK LMPG of 90mpg.
Below about 40mph on A roads or 50mph on dual carrigeways/motorways in UK you become too much of a hindrance to other road users, and are liable to be involved in an accident. Usually due to impatience in overtaking.
You would never get away with pulse and glide here for more than a few miles on a deserted country road at 3am Peter
I don't think there is any one best speed, assuming that you're driving practically rather than going for hypermiling records. It seems to depend on what sort of road you're driving on, the kind of pavement, wind, as well as imponderable things like maybe the phase of the moon.
If I'm climbing a lot of hills, I think I actually get better mpg at higher speed, because I can stay in a higher gear while keeping the engine at optimum RPM. And on downhills, going as fast as gravity allows gives better mpg (though of course this needs to be tempered by practical considerations)
It seems that the only real answer is the old "your mileage may vary"
If I'm climbing a lot of hills, I think I actually get better mpg at higher speed, because I can stay in a higher gear while keeping the engine at optimum RPM. And on downhills, going as fast as gravity allows gives better mpg (though of course this needs to be tempered by practical considerations
)It seems that the only real answer is the old "your mileage may vary"
I for one believe you're right about that. Perhaps the question would have been better put were the man to ask about engine RPM as opposed to MPH/KPM for the vehicle.james said:
On this end and taking in to account all other driving conditions and circumstances, experience is repeatedly showing me that when and where practical to do so, a 2000 RPM engine speed will result in a gound speed of about forty to fifty miles per hour which in turn consistantly results in some rather good MPG figures.
These little cars are really very good long range runners and if given half a chance, as delicate, as touchy as that gas peddle is, given the opportunity these little cars will often exceed the advertised MPG claims as offered by the manufacturer.
Fred
Proud Owner of "The Silver Bullet"
p.s. Want to have some mental fun? Next time you go by a gas station, note the price, then divide by two, then round down to the nearest quarter dollar; that's how good these little Insights are.
Even RPM isn't a constant. For instance, when I'm driving to the Bay Area, I usually fill up at the north end of Carson City. There's about 5 miles of almost imperceptable downhill through the city, and if I'm lucky enough to make all the lights, I can do it at about 30 mph in 5th, with the engine barely idling. If I reset a trip meter at the gas station, the mpg readout will be over 100 mpg. Doing the same drive in 3rd, which gives something over 2K RPM, gives maybe 80 mpg.
Going the other way, though, in 3rd I get about the same 80 mpg, but in 5th (if I can do it without lugging the engine), mpg drops to around 50, and the assist comes on.
Going the other way, though, in 3rd I get about the same 80 mpg, but in 5th (if I can do it without lugging the engine), mpg drops to around 50, and the assist comes on.
I wasn't suggesting that RPM should be a constant, it's just not a practical goal when driving BUT when and where the opportunity presents itself, on a straight away, on a long distance, ten, twenty or so mile run or more, slow down as you've been doing and try to run along at about forty or fifty MPH, which should be about 2000 RPM indicated - and watch that MPG readout soar! Just watch for that very, very sensative gas pedel. If you haven't already found out, it doesn't take very much at all in the way of a very slight movement by way of your foot to increase or decrease that MPG readout.
By the way I forgot to mention, best of luck with that "new" little car of yours!
Fred (Proud Owner of The Silver Bullet)
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In a CVT-equipped car, the gear ratio is altered to keep a CONSTANT rpm. Honda knows that there is a certain rpm that is ideal for maximum fuel efficiency.
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Read some more about the CVT Troy. It can and _does_ vary RPM depending on load.
Just like the title of this thread led to some slightly oversimplified answers (althought under "no" load and level conditions without headwinds or tailwinds 40 MPH is pretty close to optimum MPH for max MPG. But also requires proper gas pedal technique (lightest possible pressure to _maintain_ speed).
Maximum MPG RPM is closely related (in a 5 speed) to 40 MPH in 5th gear, but as has been noted eariler in this thread there are many "exceptions".
It can and _does_ vary RPM depending on load.Just like the title of this thread led to some slightly oversimplified answers (althought under "no" load and level conditions without headwinds or tailwinds 40 MPH is pretty close to optimum MPH for max MPG. But also requires proper gas pedal technique (lightest possible pressure to _maintain_ speed).
Maximum MPG RPM is closely related (in a 5 speed) to 40 MPH in 5th gear, but as has been noted eariler in this thread there are many "exceptions".
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Barely. When I testdrove the CVT civic, and pressed down the pedal, it moved from 2100 to 2200. Wow. Not much of a difference.Insightful Trekker said:Read some more about the CVT Troy.
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Then all I can reply is the load you added wasn't very much.
I've driven several CVT's over the years. Your missing the understanding of how such systems work. Similar to a downshift in a conventional automatic the CVT can and will _significantly_ change ratio (read: rev up the engine) to allow faster acceleration in response to demands of gas pedal pressure, beginning engine RPM, speed and load.
How much of a change you say :?:
Of course it depends...
I've driven several CVT's over the years. Your missing the understanding of how such systems work. Similar to a downshift in a conventional automatic the CVT can and will _significantly_ change ratio (read: rev up the engine) to allow faster acceleration in response to demands of gas pedal pressure, beginning engine RPM, speed and load.
How much of a change you say :?:
Of course it depends...
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