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I was just reading an article in popular science about the American release of "Smart" cars.
They did a 1500 mile journey with the vehicle to test it's so called "amazing" gas mileage. Of course, the vehicle is only 8.8 feet long, and weighs around 1200 lbs, so you'd expect it do great. The average mileage; 35mpg.
WTF?!?
How can a car hailed as the most fuel efficient passenger car on the market get fewer miles per gallon than my 1997 saturn?!?! Is this seriously the best we can do? I'm fuckin' dissapointed with the auto industry right now. When I heard of this car originally they were claiming efficiencies upwards of 100 mpg.
I should mention, the thing that really surprised me about the article was that Popular Science presented it as though this car was going to revolutionize the world with it's amazing mileage. Then they backup the hype with terrible stats, and pretend they didn't just make fun of themselves
So am I really the only one who's offended by this "clean" vehicle? It's 100% talk, and nothing to back it up.
I'm sick of companies jumping on the "green bandwagon" because it'll make them money, but they don't actually give two shits weather they help or not, they just want to market a different demographic.
It is actually worse. You would have to work pretty hard to get a car that is only 1200 pounds with that body shape to consume petrol at a rate of 35mpg. The first car I ever owned got the same gas mileage, at least on the interstate...
-------------------- Just another spore in the wind.
It could be all in the physics have to factor in fuel consumption per cylinder per revolutions per minute explained as cycles of fuel injection per stroke. So wile you travel at 65 miles per hour at 2000 revolutions on 4 cylinders your fuel consumption would be doubled at 4000 and your speed would not significantly increase. factor this cars only got 3 cylinders and put in at the same 2000 revolutions it would probably have to consume more fuel per cylinder to keep up to speeds. I could be picturing it wrong it's late i will do some calculations tomorrow. just picture a one cylinder engine with large cc's it consumes more fuel per revolution to compensate it's need for the stereoscopic air:fuel mixture. then factor in air resistance. and wheel diameter but a lighter car should get better gas mileage per horsepower. I'll wait till tomorrow . think about a 20 valve at 8000 rpms will consume quadruple it 2000 rpm fuel rate running at exactly the same air:fuel for eather given engine speed.
Force required to overcome air resistance is approximately equal to 1/2 rho cda v^2 where rho=1.2 (density of air), cda is the coefficient of drag times the projected frontal surface area, and v^2 is the square of the velocity. The shape of the car is going to have a very low cda compared to most cars on the road. They all have the same velocity, more or less. To find the power required to move, simply multiple by velocity again. We now end up with a v^3, which means the power required to move through the air is almost entirely due to velocity (a cubic function) and little else.
> and wheel diameter
Wheel diameter has little, if any effect. Number of contact points with the road (number of tires) and coefficients of rolling resistance per tire do matter. You also have resistance in the bearings, so there are really two rolling resistances, crr1 for tire to road contact and crr2 for bearing resistance. All of these will be directly effected by weight and by velocity. The force to overcome these frictions, based upon velocity, is a linear function, rather than a square. It becomes a squared function if we are looking at how much power is required to move (again, because we multiple by velocity).
-------------------- Just another spore in the wind.
Quote: Purple_spore said: check this out, they already have turbo kits for it. Have you seen this web-site if not check it out. http://www.fq101.co.uk/engineswap.asp
The whole rear sub-frame comes out, might just be the easiest engine removal ever.
Quote: ApJunkie said: I was just reading an article in popular science about the American release of "Smart" cars. They did a 1500 mile journey with the vehicle to test it's so called "amazing" gas mileage. Of course, the vehicle is only 8.8 feet long, and weighs around 1200 lbs, so you'd expect it do great. The average mileage; 35mpg.
WTF?!?
How can a car hailed as the most fuel efficient passenger car on the market get fewer miles per gallon than my 1997 saturn?!?! Is this seriously the best we can do? I'm fuckin' dissapointed with the auto industry right now. When I heard of this car originally they were claiming efficiencies upwards of 100 mpg.
the fabric of the universe begins to unravel
-------------------- Let it not be remembered That mycelium eats detritus and dies But that life in all it's glory Counts mycelium to be on it's side.
AFAIK, smart cars were originally developed to be cars that are easy to find parking spots for, not to boast astonishing gas mileage. I think they began to market them as super-fuel efficient cars as an opportunistic reaction to the so-called gas crisis.
And that 35 mpg figure sounds suspect. FWIW, wikipedia says "The Smart averages 4.7 L/100 km (50 mpg or 21.3 km/L) for the gasoline model and 3.4 L/100 km (69 mpg or 29.4 km/L) for the diesel."
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Welcome evermore to gods and men is the self-helping man. For him all doors are flung wide: him all tongues greet, all honors crown, all eyes follow with desire. Our love goes out to him and embraces him, because he did not need it.
Well the resistance should not matter when it comes down to engine speed. Drag weight rotating mass all factor into reducing available power at a given engine speed. I never factored in throttle position and OBD's ability to calculate injector pulses. If the cars onboard lets more fuel into the cylinders when on wide open throttle then can suck air into the cylinders thus resulting in poor atomization thus reducing fuel mileage. now this particular car is only available in a 3 cylinder turbocharged engine and will considerably reduce fuel mileage capacity on heavy throttle. and it's only .7 liters so it couldn't theoretically use that much fuel. It's has a dsg transmission and that hurts it also. I do think that particular test is a little off because in theory it should get better gas mileage then 35mpg with a conservative driver.
quote from wikipedia "The Smart averages 4.7 L/100 km (50 mpg or 21.3 km/L) for the gasoline model and 3.4 L/100 km (69 mpg or 29.4 km/L) for the diesel."
I think thats a little closer with a conservative driver with not to much change in rpm's or heavy boost presser. So In other words It could vary dramatically with this particular car.
sorry apjunkie i think it's bullshit I'm going with the .7 litters as my determining factor.
Quote: Purple_spore said: quote from wikipedia "The Smart averages 4.7 L/100 km (50 mpg or 21.3 km/L) for the gasoline model and 3.4 L/100 km (69 mpg or 29.4 km/L) for the diesel."
I think thats a little closer with a conservative driver with not to much change in rpm's or heavy boost presser. So In other words It could vary dramatically with this particular car.
sorry apjunkie i think it's bullshit I'm going with the .7 litters as my determining factor.
you can call bullshit all you want, but that doesn't change the fact that I have a published article sitting right in front of me. I'm going to call bullshit on the encyclopedia. Yay! we're both equally correct!
Quote: Marshall Michigan to Wilmington Illinois:7.89 Gallons, 37 mpg. Wilmington, Illinois to St. Louis, Missouri:8.35 gallons, 33 mpg St. Louis, Missouri to Memphis Tennessee:7.89 gallons, 34 mpg
I saw one near my house yesterday. Looked pretty sweet. If I get one I'll tint the windows and get black rims, make it all black on black on black on black, yea...
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