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Re: Big changes
kenish   8/31/2012 5:42:08 PM
@Nancy- You need to put your teens on a CAFE standard. "Mom's Cafe" dishes out 2500 calories per day and their metabolism needs to be efficient enough to power through a day on that allotment :-)

Rob Spiegel
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Re: Big changes
Rob Spiegel   8/31/2012 5:08:51 PM
So, Chuck, it sounds like automakers won't be able to slide by the rules by calling everything a truck.

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Re: Still not good enough
JimF   8/30/2012 6:58:08 PM

I would have to agree with you based on both anecdotal and spec sheet comparisons. A friend has a 2010 VW Tiguan and I drive, on most occasions, a 2006 Kia Sedona. Although he has a heavier foot than I do and drives on city streets more often our average MPG is about the same. I know this is not exactly laboratory testing but the results were surprising.

When you compare the relative spec sheets your observation seems to continue to hold true.  At almost 1000 pounds heavier, I am a little surprised at the EPA numbers.

2010 VW Tiguan

2.0-liter in-line 4 turbocharged
200 horsepower @ 5100 rpm
207 lb.-ft. of torque @ 1700-5000 rpm
EPA city/highway fuel economy: 18/24 (automatic)

Curb weight 3433

2006 Kia Sedona SE

3.8-liter V6

263 horsepower @6000 rpm

257 lb.-ft. of torque @4,500 rpm

EPA city/highway fuel economy: 16/23

Curb weight 4387



Don in Milwaukee
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True cost of oil
Don in Milwaukee   8/30/2012 3:30:10 PM
Most of the commentary on this article does "cost payoff" analysis by assuming the price of gas is around $4-$5/gallon.  Unofortunately this is a taking very constrained view.  (When engineers learn to solve problems in school, are they ever taught to "look at the whole system?")  The US imports around 600 to 800 million barrels of oil annually from the Persian Gulf.  That works out to 2.5 x 10^10 gallons/year.  Much of our Defense Dept budget goes to guaranteeing access to this oil.  So, let's suppose that we moved half of the DOD budget from the income tax to the gas tax.  That works out to raising $3 x 10^11 /year via the gas tax.  In addition, let's put the $1 Trillion (1 x 10^12) cost of the Second Iraq War onto the gas tax, paying the war off in 10 years.  That adds another $1x10^11/yr that needs to be raised to pay for our gasoline.  In other words, to tax individuals according to benefits received, the Federal gas tax should raise $4 x 10^11/year.  Annual gasoline consumption in the US is around 1.3 x 10^11 gal/year.  So, the cost-benefit discussions should be using a price of around $7-$8/gallon, not $4-$5/gallon.

Even $7-$8 is too cheap when you consider that we're at global Peak Oil.

For what it's worth, a couple of years ago I worked on a project to turn a standard 18-wheeler into a full hybrid.  Fuel economy improved by 30% in city driving, with a payoff time of around 5 years.  In grad school (1975-1976) I worked to convert a Ford Pinto into a "flywheel" hybrid.  It got 57 mpg on an EPA city cycle.  (I'm glad that today's hybrids use batteries instead of flywheels!)  So this newly announced fuel standard is quite achievable, and will provide a nice payoff if we can reduce our dependence on Persian Gulf oil.

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Re: all for mo MPG - but who is mandating ?
GW4theMechanic   8/30/2012 1:33:47 PM
You have thoroughly read Article I of the Constitution.

You also need to read Article II of the Constitution.

The EPA and DOT are part of the executive branch and are therefore "managed" by the President. This isn't the first President to set CAFE standards and he won't be the last. This has been going on since President Nixon dealt with the original Arab Oil Crisis in 1973. The Congress voted to create the EPA and DOT. After that, the President's job is to determine executive policy.

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all for mo MPG - but who is mandating ?
motorhead   8/30/2012 12:09:23 PM
My copy of the Constitution says Congress debates and passes laws.

Now the EPA and DOT does it without Congressional oversight?  Obozo circumvents something that has served us pretty well for over 200 years.  Sounds like something a dictator would do.

1270 page document to implement yet another mandate that has been rammed down our throats.

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Re: Still not good enough
Bunter   8/30/2012 11:57:13 AM
Hi Jim (and naperlou),

Just thought I would throw in an observation I have made regarding smaller high output engines and mpg. The cases I'm thinking about are primarily turbo 4 or 6 to replace NA 6 or 8, but some times a high rpm 4 to substitue for a 6.

Generally this does give a higher EPA number than the larger engine.  However in road test data (I read many, online/paper, car mags to CR) this does not typically pan out.  I have not spreadsheet the data, but my observation is that on the road, back-to-back, same drivers etc., the mpg of similar vehicles (purpose, mass, drive train-that is 2wd or 4wd) with similar horsepower does not vary greatly.  It is not uncommon for the smaller turbo to get poorer mpg.

I suspect the problem is that the EPA cycle has a very low demand on acceleration (I've heard) and it may rarely invoke the boost on a turbo engine (or high rpm in the applicable cases).  In the real world people do use the capability of the turbo engine and the amount of fuel-air mixture processed by the engine is similar (same amount compressed into the smaller combustion chamber) to that of the larger NA engine.

Any thoughts?



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Re: Still not good enough
JimF   8/29/2012 10:13:06 PM
naperlou I agree with your observation regarding automobile manufacturers getting more power out of the same size engines rather than looking for more efficiency at the same power levels. I suspect that is in part related to the increased heft in same "sized" cars. I had a 1992 Honda Civic that got on average, 38 MPG. The Honda Civic today is just approaching that MPG figure and is producing about 40 more HP. it also weighs about 380 lbs more than my car. Because we seem to need all sorts of "tools" in the drivers seat these days which distract us we also need a bunch of safety gear to keep us alive. Airbags that deploy from all directions, collision avoidance sensors and others add weight. I won't even get into the necessity of automated parking.

User Rank
Re: Big changes
robatnorcross   8/29/2012 8:44:30 PM
 I'm wondering what genius/lawyer/bureaucrat in D.C. was able to calculate the 55.5 number. why not 54 or 56 or 88. Hell why not go for 180 mpg if your pulling numbers out of your a**. The reason cars cost so much now is all of the mandates they have put on over the years.

I can't figure out how I ever lived through childhood riding in my families 55 Chev. No seat belts, no electronic tire inflation transmitters, no engine control modules; only steel dash boards to give me brain damage and non rubberized knobs on radios to gouge my eyes out if I was too stupid to pay attention.

William K.
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Big changes & 54.5MPG CArs
William K.   8/29/2012 6:47:21 PM
Evidently my first post did not make it. 

I offer the fact that it is difficult to force people to purchase cars that they don't like and don't want. Also, it will be quite a challenge to make people drive cars that don't provide any of the comforts and conveniences that they are used to. 

I really don't think that the auto companies are stupid, not at all. They do market research, and try to provide the cars that people will want to buy. Sometimes they are a bit behind the curve, when fads change to rapidly, but mostly they deliver what people want, or fairly close to it. 

The problem seems to be that the 55MPG car does not seem to be the sort of vehicle that most folks would choose, unless it winds up also costing a lot less. I might buy a very small car with much less power and performance if it were a lot cheaper than a normal car, but I absolutely refuse to consider buying one for the same price as my current vehicle, which is comfortable and reasonably fuel efficient. So the real challenge will be to find a way to force people to drive cars that they don't want to drive, or even purchase, without appearing to be taking away their freedoms. 

Of course, if there were some compromises made on some of the other mandatory feature that we have now, the cost could be less. but I don't see any willingness to compromise on any of the current mandates.

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