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Old 12-31-2005, 03:12 AM
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MPG Differences (USA and UK)

Specifically curious about the Elise:

City ("Urban" in UK) is quoted as 23mpg in both countries.
Highway ("Extra Urban") is 41.4mpg in the UK and 27mpg in the US.

These figures come from Lotus for the Standard US Elise and the 111R in the UK which has the same engine. I know that 41mpg is realistic from having talked to owners who have said as high as 39mpg on long trips. So I'm wondering what's different about the testing?

I must say that I'm a little suspicious of the numbers only because the UK Exige (standard and 240R!) is listed as having the same milage as the 111R yet its (slightly) heavier and has a higer Cd. So if Lotus is just copying and pasting from car to car they might not be accurate. But that doesn't change the fact that ~40mpg is possible.
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Old 12-31-2005, 03:52 AM
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I gave this answer to a very similar question a while back

1) - UK gallons are bigger than silly little US gallons:
1 UK Imperial Gallon = 4.55 litres
1 US Liquid Gallon = 3.79 litres

2) - UK mpg figures will be calculated using the EU's methods, the US mpg figures will be calculated using the EPS's methods.

They are different, and the different cycles (Urban, Extra-Urban and Combined for the EU, City and Highway for the EPA) don't directly compare.

Neither sets of figures actually replicate real-world driving, so they are best used as a guideline to compare against other vehicles, rather than used as an actual indicator of fuel efficiency.

The lack of accuracy in the mpg figures is compounded by other factors such as; driving with aircon on, roof/windows up/down, different tyres, ambient temperature, road surface - things which affect the rolling resistance and drag of the car, and the work load on the engine.

Fuel in the USA and UK is also different, and not only that, but different fuels give different efficiencies.

Comparative consuptions for the Elise 111R: (mpl = miles per litre)
EU Urban Cycle: 23.3mpg* = 5.1 mpl
EU Extra Urban Cycle: 41.4mpg* = 9.1 mpl
EU Combined Cycle: 32.1mpg* = 7.1 mpl

US City cycle: 23mpg** = 6.1 mpl
US Highway cycle: 27mpg** = 7.1 mpl

* - UK mpg
** - US mpg
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Last edited by Coventrysucks; 12-31-2005 at 04:12 AM.
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Old 12-31-2005, 04:27 AM
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another proof of the stupidity of some countries refusing to adopt the metric system
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Old 12-31-2005, 04:51 AM
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Quote:
Originally Posted by henk4
another proof of the stupidity of some countries refusing to adopt the metric system
I suppose that it theory it might sound nice to have a global benchmark, so that all manufacturers produced figures in l/100km (Lots of European manufacturers have taken to publishing l/100km and PS alongside mpg and bhp for the UK market, so it won't be long now...), however the differences in the quality of fuels means that fuel consuption would still not be directly comparable from country to country.
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Old 12-31-2005, 04:53 AM
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CS, the "metric" consumption should be given in litres per kilometre.
Mixing the British way round and one imperial and one metric scale is VERY confusing ( as ever driven by the UKs slow move to metrication ). We dont' really need another half-baked measurement in the world, do we ??

Which mag published these ???? Or was it Lotus ?????
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Old 12-31-2005, 10:49 AM
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Quote:
Originally Posted by henk4
another proof of the stupidity of some countries refusing to adopt the metric system
No the other system is superior since... since...
uuh...
yeah, since more Americans are used to it and isn't that what really counts? Metric is anti-American anyway.
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Old 12-31-2005, 12:18 PM
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Yeah its true. The only class in which i NEED to know metric is my Chemistry class. And its just simple stuff. I was goin to say the difference is most american drivers are very careless and drive thier cars rediculiously hard. Causing MPG to drop. Example, i have a friend who has a Hemi Dodge Ram, and he usually gets about 12 -14 mpg, but he smokes the tires often cause, well i have no clue why, and he gets about 8 or 9 mpg now. But the explaination above clears my theory up.
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Old 12-31-2005, 03:14 PM
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I have had four years of college classes using both metric and american units and this is the fist time ive heard about the difference in gallons, then again, the UK version of the gallon is not considered metric. Does anybody in the rest of Europe use (this version of) gallons?
Thanks, Coventry.

I guess this means there must be a big difference in testing. How else could a US car get 20% better milage in the city but 20% worse milage on the highway?

Matra, the figures are from Lotus UK and USA sites.
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Old 12-31-2005, 03:17 PM
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Quote:
Originally Posted by henk4
another proof of the stupidity of some countries refusing to adopt the metric system
I hear you!
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Old 12-31-2005, 08:25 PM
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it is anti patriotic to even speak of the metric system.
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Old 01-01-2006, 09:55 AM
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Wow,
So many cleaver people who don't live in the US have such insight into the US.

I suppose that would be just as we researched as if I said Europeans are snobs because I [sarcasm]know [/sarcasm] it to be true

The US "officially" adopted the metric system well over a century ago. The issue is converting EVERYTHING over. As our friends in England I'm sure can tell you it's isn't always easy. However, all of my work is don't in the metric system. When I worked in combustion engineering that wasn't as easy because units of entropy don't always convert well.
Personally, I think switching over is a good idea but much like England, I think switching things like miles to kilometers is not that important but actually would cost quite a bit. Half the street signs in the US would have to be changed. ALL of our interstate exits (numbered based on mile marker) would have to change. That’s a BIG impact for what is honestly not a big problem. I mean aside from the fact that it gives Europe something to be snooty about.

As for mpg vs L/100km, well distance per unit consumed is a more typical definition of efficiency but L/100km has some benefits. I don't like that it's not a unit to unit measurement. The 100 part seems improper and rather... like a British unit of measurement. The advantage to the fuel used per distance method is it really shows the difference between say 10 and 12 mpg (20%) as a big deal while the distance per fuel consumed shows it to be just two extra miles. While 40 to 44 mpg looks like a more impressive 4 miles extra it's only a 10% improvement.

PS: Euro snobbery is no more attractive or warranted than American snobbery. Both are distasteful and really not worthy of what is a well run forum.
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Old 01-01-2006, 10:05 AM
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we actually did switch over to metric officially in the late 70s... it lasted for about 15 minutes before us progressive americans said HELL NO, and we switched promptly back to our tried and true, and mildly retarded, old ways of doing business
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Old 01-01-2006, 10:16 AM
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Quote:
Originally Posted by culver
Wow,
So many cleaver people who don't live in the US have such insight into the US.

I suppose that would be just as we researched as if I said Europeans are snobs because I [sarcasm]know [/sarcasm] it to be true

The US "officially" adopted the metric system well over a century ago. The issue is converting EVERYTHING over. As our friends in England I'm sure can tell you it's isn't always easy. However, all of my work is don't in the metric system. When I worked in combustion engineering that wasn't as easy because units of entropy don't always convert well.
Personally, I think switching over is a good idea but much like England, I think switching things like miles to kilometers is not that important but actually would cost quite a bit. Half the street signs in the US would have to be changed. ALL of our interstate exits (numbered based on mile marker) would have to change. Thatís a BIG impact for what is honestly not a big problem. I mean aside from the fact that it gives Europe something to be snooty about.

As for mpg vs L/100km, well distance per unit consumed is a more typical definition of efficiency but L/100km has some benefits. I don't like that it's not a unit to unit measurement. The 100 part seems improper and rather... like a British unit of measurement. The advantage to the fuel used per distance method is it really shows the difference between say 10 and 12 mpg (20%) as a big deal while the distance per fuel consumed shows it to be just two extra miles. While 40 to 44 mpg looks like a more impressive 4 miles extra it's only a 10% improvement.

PS: Euro snobbery is no more attractive or warranted than American snobbery. Both are distasteful and really not worthy of what is a well run forum.
interesting propositions. My snear at the users of the non-metric system was mainly induced by the fact that they even are not capable to talk about the same gallon.......

In Europe there is a constant controversy about using the "mileage" units as well. We used to say : A car will do so many km using 1 litre, but then it was made official to talk about so many liters per 100 km.

Furthermore there is still the "official" power measurement of engines, which should now be in KW and not BHP. It has not yet been generally accepted, most likey for the psychological reason that BHP gives a more flattering (higher) figure than KW.

Anyway, Canada was perfectly capable to go metric, also in distances, so the USA could do the same easily
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Old 01-01-2006, 10:59 AM
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Quote:
Originally Posted by culver
Wow,
So many cleaver people who don't live in the US have such insight into the US.
.........
PS: Euro snobbery is no more attractive or warranted than American snobbery. Both are distasteful and really not worthy of what is a well run forum.
Reading FAR too much into it IMHO

The difference between US and Imperial has nothing to do with metric and MUCH more to do with variances in shipping companies barrel sizes and a desire to distance from teh "Kings" measurements - old history

BUT to come up with miles per litre is an odd mix. The choice to go with litres/100km DID make sense as it IS called "fuel CONSUMPTION" so hence usage of fuel per unit distance is the correct units. MEasuring ful consumption by distance traveled per unit fuel isn't really "consumption" it's "usage".

MANY SI units use non-base multipliers to express numbers in sensible units. It's shown that most dont' understand ratios expressed in their "normalised" 0-1 range with decimals and instead are used to the 'percentage' == per 100. So nothign knew in expressing it in 100kms really


It all makes sense when you can go back to the root etymology and definitions.
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Old 01-01-2006, 11:21 AM
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C'moon culver, where's your sense of humour. Did you try to indicate that we Europeans behaved like snobs since we questioned the logic of the American system? You raised some good points aswell, but when it comes to changing it's all about will. To change a system to (global) standards costs, but usually saves money in the future.

anyway I guess some of the sarcastic remarks above are related to views expressed in this thread:
http://www.ultimatecarpage.com/forum...t=21507&page=3
check this thread from reply 32 onwards for a laugh.

Quote:
Originally Posted by culver
Wow,
So many cleaver people who don't live in the US have such insight into the US.
It's amazing how you get a bigger picture if you take a step back
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