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Fuel Efficiency Numbers Overstate MPG More For Cars With Small Engines
whoever57 writes: All official numbers for fuel economy in the EU typically overstate the miles-per-gallon figure that drivers can expect to achieve in typical driving. A recent study confirmed this once again. However, what the study also found was that MPG figures are more unrealistic for cars with smaller engines than for cars with larger engines. Actual MPG figures achieved based on typical drives for cars with small engines could be as much as 36% under the official number, while those cars with 3-liter engines would typically achieve 15% less than the official figure.
These discrepancies need to be accounted for if we're going to be serious about regulating fuel efficiency. But then, we should be using gallons-per-mile instead of miles-per-gallon, too.
If you try to push a small engine to drive like a larger one, you'll be accelerating harder, therefore using more fuel than under normal acceleration.
In similar manner, some years ago, I had a Grand Cherokee that my wife couldn't get more than 11mpg out of, while I could do 17mpg.
We have different driving styles. She is a leadfoot, while I drive like I have an uncooked egg between my foot and the gas pedal.
Perhaps this article might better be titled "Want better gas mileage? Don't drive like a gashole."
The shepherds did so well protecting the flock that the sheep no longer believed that wolves existed.
1 US gallon / mile = 0.00364583333 sq inches
Some drink at the fountain of knowledge. Others just gargle.
(that being the USofA) is to worry about how far we can go on a tank of fuel. This is a throwback to the days when trips of any significant distance could easily leave you stranded between fueling stations (which used to be as much as hundreds of miles apart)
In that case, knowing distance per unit of fuel is more important than fuel per unit of distance.
In Europe, where distances are SIGNIFCANTLY shorter it is much more interesting to worry about the cost of the trip, especially when public transport options are close competitors in price. In this case the unit of fuel per unit of distance makes a much easier comparison.
The reason it's considered inferior is because it's inverted from what you really care about - what you care about is "how much fuel will it take me to get n miles".
No, what I really care about is, "can I make it to the next fuel stop with what I have in the tank." Which is not a problem in most of Europe, but is very much a problem in large parts of the USA.
And unlike the manufacturers' economy claims, I use the number on a regular basis instead of just when I'm planning to buy a car.
Lacking <sarcasm> tags,
Now lets try the same using the metric system:
1 litre / kilometre = 1 sq millimetre
That is another win for the metric system in my book.