When I started looking at PriusChat a few weeks ago it was news to me that the American gallon is less than the Imperial gallon sold in the UK. Also that Canadians use litres/100 kms, not MPG. Even in the UK, MPG is not used so much since fuel has been sold in litres since the 1960s, although most cars still record miles on their odometers and road signs give distances in miles, so things are still confused. This must make the useful discussions here about MPG even more confusing to foreigners. I'm not much good at mathematics but I compiled the following little table which I hope will be helpful (my apologies if someone has already done something like this in an earlier topic): [attachmentid=701] After that I became curious so I did a bit of research. Why is there a different gallon on the other side of the pond? It's well known that measures of all kinds were chaotic almost everywhere until the late 19th century but one would have thought that by the time the ICE was coming on to our roads in the 1890s the gallons would have been sorted out. Even as far back as 1790 George Washington gave some thought to the matter. In his first message to Congress he pointed to the need for "uniformity in currency, weights and measures." In those days there was the "wine gallon" of 231 cubic inches and the "ale gallon" of 282 cubic inches. In 1824 the British (who always preferred ale to wine anyway) decided to abandon the wine gallon (known as Queen Anne's gallon) but the Americans have stuck to it to this day. Queen Anne (1665-1714) reigned from 1706.
There are many sites for doing conversions. Here is one that is useful: http://www.simetric.co.uk/index.htm First introduced by Thomas Jefferson, the US System of measurement is SI by the Acts of 1866, 1975, 1988 and other Acts. It is bizarre that we drive vehicles with Liter displacement and made to SI standards, but can only purchase oil in quarts (not Liters) and gasoline in gallons (not Liters).
The quick-n-dirty conversion factors I use: 235/MPG (US) = L/100km 235/L/100km = MPG (US) MPG(UK) = 1.2 * MPG(US)
Actually, you can just use google. Search for "18 mpg in litres/km" or "18 miles per gallon in miles per imperial gallon" Google does hundreds of unit conversions, quick & easy.
Well, i thas only been in the past decade or so that metric designations for displacement came in vogue in the USA. Famous motors were 427,327, 408, 225, 289, 283, etc....ask your father B)
Units of measurement have to be about the least logical thing around...except for metric. Which is heavier, an ounce of feathers, or an ounce of gold? You think I'm kidding, don't you? Well, there is a correct answer, and it's not 'neither'. Feathers are measured in 'avoirdupois' ounces (the normal kind), which are 28 grams each. Gold is measured in Troy ounces, which are 31 grams each. So, an ounce of gold is heavier than an ounce of feathers. Here's the bonus question: Which is heavier, a pound of gold, or a pound of feathers? No, it's not the same answer. Avoirdupois ounces come 16 to the pound, and troy ounces come 12 to the pound. So, a pound of feathers is heavier than a pound of gold. No, I'm not making this up. I'm convinced some English king had 12 fingers and 12 toes.
oxo and hyo: thanks! Love it! I taught U.S. history and didn't know about the wine gallon, the gold or the feathers. I also had no idea the UK used miles. Big surprise! Also: 4-0-9 (Beach Boys!), 390 & 302 (Ford), 305 (Chevy small block, 70's) Anyone know why Dee-troit started using litres as a measure of engine displacement? I think the first I heard of it was with respect to some humungous Cadillac engine, maybe in the 80's---8 L or so? Was it during one of our many false starts in adopting the metric system---or just a marketing thang?
Mostly from Encyclopaedia Britannica (1974 edition). In the article "Weights and Measures" there's a long history with much detail. I knew the conversion tables could be found on the web but I wanted something small and handy on paper that I could stick on my monitor when I'm reading about all the MPG on PriusChat!
If you think THAT is confusing, try living less than an hours drive from the United States, like most Canadians do. A "gallon" is NOT a "gallon" though a mile is still a mile. I'm a dual citizen and as a kid spent about an equal amount of time in both countries. Maybe that's why my math skills were so good, I was forced to mentally convert gallons to "gallons." AFAIK the U.S. gallon, U.S. quart, etc, is only used in the United States. Imperial gallon, Imperial quart, etc was used in the rest of the world. I'm surprised to hear that in the UK velocity is still in miles per hour. I've never had to drive in the UK though, I have had plane changes at Heathrow. In Canada the odometer has been metric since the 1980's maybe a bit earlier. Speed in km/h distance in km. When you look at a new car, the information sticker has fuel economy in l/100km, with the translation to MPG in much smaller print.
