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This test clearly shows exactly what I've been telling people since I got my Fiat, its a car designed to be economical in the real word...not just designed to get specific EPA numbers on some test. Every other car seems to miss its mark in matching the fuel economy sticker on the window when you buy it. The reason is blatantly obvious, car makers are making cars they can "market" as 40 MPG...not cars that get 40 mpg.

I have a Fiat 500c automatic and am averaging 34.6 mpg with much of my travel being city driving in traffic during rush hour. This is at least 5 mpg better than I'm "supposed to get." The Fiat is designed to BE efficient...not just pretend on commercials and window stickers.
 

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I would have went with a Golf TDI, much nicer inside than the new Jetta, and it is a hatch. I know they say they couldn't get a Fiesta, but I would really love to see how that would have compared, or a new Mazda3 Skyactive.
 

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I was just being sarcastic....that's the NYC in me. I hope you were able to read the link.
 

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it looks like they are usuing the manualt trans 500, whhich is to be expected.

quite honestly, a car this tiny should be getting better economy than those other cars except the tdi. if it didnt that would be a bit lame.
 

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I would have went with a Golf TDI, much nicer inside than the new Jetta, and it is a hatch. I know they say they couldn't get a Fiesta, but I would really love to see how that would have compared, or a new Mazda3 Skyactive.
I would like to see the CR-Z. I know, with my self included, many have seen much better than MPG's than what is on the sticker. Between high 50's and low 60's MPH on flat highway you could get 50 MPG easy in ECON mode.
 

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If you factor in base price this is a total smack down. In Canada you can get a 500 pop for like $14000. TDI anything is almost double, Volt is like $87000 or somthing crazy, and the Koreans don't come close to the EPA ratings. S M A C K D O W N!
 

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it looks like they are usuing the manualt trans 500, whhich is to be expected.

quite honestly, a car this tiny should be getting better economy than those other cars except the tdi. if it didnt that would be a bit lame.
Well, it is a great article. What I get from it is that the car is better than people think.
;)
 

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it looks like they are usuing the manualt trans 500, whhich is to be expected.

quite honestly, a car this tiny should be getting better economy than those other cars except the tdi. if it didnt that would be a bit lame.
Hi,

I quite a bit disagree. Its not uncommon for relatively small cars to be less aerodynamic than a larger car, and hence it is often easier to improve the efficiency of a mid-size car than a smaller one.

Specifically here is a quote from some one from IHS named
Aaron Bragman (http://blogs.cars.com/kickingtires/...ts-and-compacts-get-such-similar-mileage.html ):

"In some cases, it’s actually harder to eke out better highway mileage in a subcompact car ... When you have a B-segment [subcompact] car, it’s very hard to make it aerodynamic, given how short it is and how many of them end abruptly”

Additionally, from this link ( http://autospeed.com/cms/title_Low-Drag-Car-Aerodynamics/A_109778/article.html ) here is another quote:

"What happens at the back of the car is extremely important in determining total drag, rear axle lift and, to a more limited extent, front axle lift. In many cases, the flow at the back of the car is more important than the flow behaviour at the front. The pattern of airflow at the rear of the car depends very much on the type of car being examined. If the airflow from the roof is to remain attached down onto the boot, a three-box sedan must have a very shallow-angled rear window. It is very important that this flow does remain attached – the area of the wake will be reduced, dramatically lowering the car’s overall Cd. When the profile of a three-box sedan is compared with an ultimate teardrop shape, it can be seen that separation at the roof/rear window transition can easily occur.

Cars with gently sloping rear windows – often hatchbacks or coupes– allow the airstream to remain attached right to the rear of the car, soproducing only a small wake. The transitional curve between the roof and thehatch needs to be gentle if the airflow is to remain attached, and the angle ofthe hatch to the horizontal is also critical. It’s important to note that whileit may look ‘obvious’ to the eye that the airflow remains attached across acoupe or hatchback’s rear, wool tuft testing needs to be carried out to prove this.

Even quite minor changes inrear hatch angle can cause major changes in drag. Tests carried out byVolkswagen have shown that the Cd of the car can vary from 0.34 to 0.44 as aresult of slight alterations to the rear hatch angle. At one angle (30 degreesto the horizontal in this case) the airflow separation point jumped back andforth from the end of the roof to the bottom of the hatch, depending upon thecurvature at the rear edge of the roof. It was this 30 degree rear hatch anglethat produced the highest Cd value. This sort of substantial change in thecar’s drag coefficient will have a large influence on the car’s top speed andfuel consumption. In some cars even a 10 per cent reduction in drag willdecrease open road fuel consumption by 5 per cent.

Cars with a near-vertical rearhatch have airflow separation that occurs at the end of the roof. This meansthat the wake is as large as the frontal cross sectional area of the car.People who locate spoilers half way down the rear hatch should realise thatthey are achieving nothing with this placement!
A large wake is also present onmost station wagon designs. For example, the Cd of the AU Ford Falcon wagon issedan is 0.341, versus the sedan’s 0.295."

In general the 500 is actually a fairly small "two box" design (http://en.wikipedia.org/wiki/Three-box_styling), and has a relatively steep slope to its aft end, probably due in part to the desire to make the rear seat spacious enough to fit people. As such, it seems to me that Fiat engineers have done a nice job getting the efficiency of the car up where they have.

Regards

Pat


 

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Hi,

I quite a bit disagree. Its not uncommon for relatively small cars to be less aerodynamic than a larger car, and hence it is often easier to improve the efficiency of a mid-size car than a smaller one.

Specifically here is a quote from some one from IHS named
Aaron Bragman (http://blogs.cars.com/kickingtires/...ts-and-compacts-get-such-similar-mileage.html ):

"In some cases, it’s actually harder to eke out better highway mileage in a subcompact car ... When you have a B-segment [subcompact] car, it’s very hard to make it aerodynamic, given how short it is and how many of them end abruptly”

Additionally, from this link ( http://autospeed.com/cms/title_Low-Drag-Car-Aerodynamics/A_109778/article.html ) here is another quote:

"What happens at the back of the car is extremely important in determining total drag, rear axle lift and, to a more limited extent, front axle lift. In many cases, the flow at the back of the car is more important than the flow behaviour at the front. The pattern of airflow at the rear of the car depends very much on the type of car being examined. If the airflow from the roof is to remain attached down onto the boot, a three-box sedan must have a very shallow-angled rear window. It is very important that this flow does remain attached – the area of the wake will be reduced, dramatically lowering the car’s overall Cd. When the profile of a three-box sedan is compared with an ultimate teardrop shape, it can be seen that separation at the roof/rear window transition can easily occur.

Cars with gently sloping rear windows – often hatchbacks or coupes– allow the airstream to remain attached right to the rear of the car, soproducing only a small wake. The transitional curve between the roof and thehatch needs to be gentle if the airflow is to remain attached, and the angle ofthe hatch to the horizontal is also critical. It’s important to note that whileit may look ‘obvious’ to the eye that the airflow remains attached across acoupe or hatchback’s rear, wool tuft testing needs to be carried out to prove this.

Even quite minor changes inrear hatch angle can cause major changes in drag. Tests carried out byVolkswagen have shown that the Cd of the car can vary from 0.34 to 0.44 as aresult of slight alterations to the rear hatch angle. At one angle (30 degreesto the horizontal in this case) the airflow separation point jumped back andforth from the end of the roof to the bottom of the hatch, depending upon thecurvature at the rear edge of the roof. It was this 30 degree rear hatch anglethat produced the highest Cd value. This sort of substantial change in thecar’s drag coefficient will have a large influence on the car’s top speed andfuel consumption. In some cars even a 10 per cent reduction in drag willdecrease open road fuel consumption by 5 per cent.

Cars with a near-vertical rearhatch have airflow separation that occurs at the end of the roof. This meansthat the wake is as large as the frontal cross sectional area of the car.People who locate spoilers half way down the rear hatch should realise thatthey are achieving nothing with this placement!
A large wake is also present onmost station wagon designs. For example, the Cd of the AU Ford Falcon wagon issedan is 0.341, versus the sedan’s 0.295."

In general the 500 is actually a fairly small "two box" design (http://en.wikipedia.org/wiki/Three-box_styling), and has a relatively steep slope to its aft end, probably due in part to the desire to make the rear seat spacious enough to fit people. As such, it seems to me that Fiat engineers have done a nice job getting the efficiency of the car up where they have.

Regards

Pat


sure, i understand all of that. however, the 500 has fair drag numbers for a hatch, and also has the advantage of a small frontal area which comes into play. more importantly, being so small has the obvious advantage of having a low curb weight....significantly lower than the other cars in the test. being that the tests were pure highway runs at constant speed, that lower curb weight is a terrific advantage.
 
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