CAFE standards vs New MPG ratings
12-29-2007, 09:34 AM
#1
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CAFE standards vs New MPG ratings
When are the more realistic MPG ratings for cars coming out? Is this a process that will change more than once? The way I see it is, my car has an almost arbitrary number written on the window sticker when the MPG testing is fudged. Some hybrid numbers are pure fantasy on the highway. What is the news on improving MPG testing and how do you think it will play in automotive design in regards to new CAFE regulations?
12-29-2007, 10:00 AM
#2
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The new MPG numbers are on the '08 cars.
I've heard that parroted around, that the old MPG numbers were fantasy, but it hasn't been my experience. I'm not speaking so much for just hybrids, which have been known to be a few MPG generous since the beginning, but for most other cars. I've had an '80Z28, '81Z28, '87TA, '88CamaroRS, '92Vette, '93Z28, '95 Accord EX, '02 Acura TL-S, and an '06 TL over the years, and I've never had an issue meeting the stated MPG numbers. In fact, I almost always best the City numbers by quite a few points, probably because I've been a suburbanite (but close-in-suburbanite, nonetheless).
I think the new testing is skewed too heavily toward over-aggressive drivers, and makes the numbers lower than they really will be. Subtlely, I think this encourages driving styles that promote increased fuel consumption, which I don't think it a good thing. It's the old "underpromise, overdeliver" BS that's really code for sandbagging, IMO. For instance, the 2006 Acura TL was rated at 20/29, and for 2008- no changes to engine, driveline, or overall weight (within 20 lbs, anyway)- is now 18/26. I have an '06, and get 22mpg going 6 miles to work, and get 30 highway at 70mph. In order to get 26, I'd have to run 90mph avg. I know this, because I once ran an entire tank at 80-90mph, and still managed 27.5mpg. In order to hit 18 city, I'd have to do a 5-10min warmup every day, and average under 20mph.
The role that these new numbers play is that the manufacturers are now further away, on paper, from the goal. I think this might be good in the end, but may also be used as a "we can't do it" excuse down the road. It's tough to see how it will play out.
I've heard that parroted around, that the old MPG numbers were fantasy, but it hasn't been my experience. I'm not speaking so much for just hybrids, which have been known to be a few MPG generous since the beginning, but for most other cars. I've had an '80Z28, '81Z28, '87TA, '88CamaroRS, '92Vette, '93Z28, '95 Accord EX, '02 Acura TL-S, and an '06 TL over the years, and I've never had an issue meeting the stated MPG numbers. In fact, I almost always best the City numbers by quite a few points, probably because I've been a suburbanite (but close-in-suburbanite, nonetheless).
I think the new testing is skewed too heavily toward over-aggressive drivers, and makes the numbers lower than they really will be. Subtlely, I think this encourages driving styles that promote increased fuel consumption, which I don't think it a good thing. It's the old "underpromise, overdeliver" BS that's really code for sandbagging, IMO. For instance, the 2006 Acura TL was rated at 20/29, and for 2008- no changes to engine, driveline, or overall weight (within 20 lbs, anyway)- is now 18/26. I have an '06, and get 22mpg going 6 miles to work, and get 30 highway at 70mph. In order to get 26, I'd have to run 90mph avg. I know this, because I once ran an entire tank at 80-90mph, and still managed 27.5mpg. In order to hit 18 city, I'd have to do a 5-10min warmup every day, and average under 20mph.
The role that these new numbers play is that the manufacturers are now further away, on paper, from the goal. I think this might be good in the end, but may also be used as a "we can't do it" excuse down the road. It's tough to see how it will play out.
12-29-2007, 03:59 PM
#3
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It really depends on how you drive the car. My Formula seems to achieve peak MPG at 55-60mph. Unfortunately in the areas I drive I hardly ever experience those speeds. I do a fair amount of highway driving where the limit is 65 or 70mph and the car is making several less MPG at those speeds. So my highway and combined averages are a lot closer to the newer standard than the old ones since I spend much more time at or above 70mph. My car is an A4 3.23 geared car though. I'm sure the 2.73 cars or especially the manuals get better mpg at higher speeds than I do.
12-30-2007, 05:37 AM
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Er, no they're not. You can't measure MPG on the electric side of it. Only the engine. Yeah, you could measure how much electricity, kWh (?), you get from 1 gallon of gasoline and see how far it goes, but burning gasoline in a generator is like putting your engine at 1500rpm and not putting variable loads (drag, A/C compressor) on it at random intervals.
Pure BS.
Pure BS.
12-30-2007, 10:01 AM
#6
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Er, no they're not. You can't measure MPG on the electric side of it. Only the engine. Yeah, you could measure how much electricity, kWh (?), you get from 1 gallon of gasoline and see how far it goes, but burning gasoline in a generator is like putting your engine at 1500rpm and not putting variable loads (drag, A/C compressor) on it at random intervals.
Pure BS.
Pure BS.
Anyway, the window sticker ratings don't change the raw numbers being used to calculate CAFE. Or did the entire FTP get overhauled so the emissions and CAFE numbers are also being run on the more aggressive schedule that is used to get the revised window sticker numbers?
12-30-2007, 11:04 AM
#7
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Er, no they're not. You can't measure MPG on the electric side of it. Only the engine. Yeah, you could measure how much electricity, kWh (?), you get from 1 gallon of gasoline and see how far it goes, but burning gasoline in a generator is like putting your engine at 1500rpm and not putting variable loads (drag, A/C compressor) on it at random intervals.
Pure BS.
Pure BS.
12-30-2007, 11:53 AM
#8
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Not really. Being closer to reality is a step in the right direction....but anyone with 3 or more working brain cells knows that hybrids are the flavor of the week and do jack **** to solving any problems.
12-30-2007, 12:19 PM
#9
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Fuel mileage is pretty simple to calculate...miles driven divided by gallons of fuel used...
They may not be "the answer," but that has jack to do with the CAFE numbers better estimating the real world mileage a hybrid owner might see.
12-30-2007, 05:37 PM
#10
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12-30-2007, 05:47 PM
#12
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Please explain yourself further. The Prius pack has no reliability problems. It's possible to argue that we're approaching our planet's capability to cough up additional nickel and lithium, but if you're going to argue that point, I'd like to see some facts.
