How Fuel efficient is your car?

[ygmir]

**edit to address this to Gyre**

how can you say there is no significance related to speed? (your 55-60 mph reference)

do you know the difference, between air flow and shockwave, as relates to a vehicle moving? how the pressure increases with speed, by forcing the air out of the way?
Many vehicles, directly related to aerodynamics, have different upper limits where speed vs airflow changes efficiency.

highest efficiency doesn't occur in a vacuum.........so, speed has to figure into the equation.

[gyre]

**edit to address this to Gyre**

how can you say there is no significance related to speed? (your 55-60 mph reference)

Easy.
I didn't say that.
I said there is nothing significant about 55 or 60 mph.
It has been presented as a magickal number for so long most never question it.
It's just another speed.

And drivetrain loss is part of the total cost, a very large factor with fwd transmissions generally, all large engines at idle and so on.

By the way, many trucks suck because they are geared inappropriately for the intended use.
Full size trucks often just need taller gearing, not that they will compete with 2000 pound cars.

[gyre]

Diesels are popular in Europe, because, as I understand it, the governments subsidize diesel prices. Our truckers would love that.

It is true about diesel pricing.
The technology has overcome that disadvantage at this point.

For pure mileage, the non-hybrids always do better.
The preferred car by the hypermilers is the older Honda Insight so far.
The CRX HF wasn't too bad either.
The Prius is a fairly big car, so the mileage is okay for its size.

the hybrid thing is strictly a stop and go obsession thing.
Remember where most of this legislation comes from.

Diesels have a huge advantage in not being as sensitive to peak load efficiency as gas engines.
They can perform deceptively better overall.
The tech has reached the point of being competitive in sports cars and race cars.
That tells the whole story.

[ygmir]

**edit to address this to Gyre**

how can you say there is no significance related to speed? (your 55-60 mph reference)

Easy.
I didn't say that.
I said there is nothing significant about 55 or 60 mph.
It has been presented as a magickal number for so long most never question it.
It's just another speed.

And drivetrain loss is part of the total cost, a very large factor with fwd transmissions generally, all large engines at idle and so on.

By the way, many trucks suck because they are geared inappropriately for the intended use.
Full size trucks often just need taller gearing, not that they will compete with 2000 pound cars.

*rolls eyes, dons football helmet, looks for tennis racquet*

[gyre]

Is that a question in some mysterious way?
Comment?


Only chicks get to expect everyone to read their minds.

[Captain Goddammit]

60 MPH is a "significant number" because that's the speed you're allowed to drive in and around most populated areas, so it's the speed lots of us are concerned with.
Recycling by driving our older cars that already exist has a lot of merit.
Trucks can really suck to drive around empty because of their gearing! My one-ton has 4:10 gears, like almost all of them, and no overdrive. It gets a lot shittier mileage than it needs to because it spins it's large displacement engine at unnecessarily high RPM, but when loaded heavy (truck/camper/trailer combo for BM trip totals 22,000 pounds) it needs those low gears.

What I don't understand is why the hell haven't they just made transmissions with a few more gears and hell of a lot wider range?
This amazingly brilliant stroke of genius has finally been creeping into production vehicles after about a hundred years of making them with a super narrow operating range, forcing people to choose rearend gears that work for only some of what they need.

[ygmir]

I'd say, a good part of manual transmissions being limited to 4 speeds historically, is, the publics (probably, and, mostly) inability to shift a trans. with more gears........after 4, it takes a lot more skill to "hit the hole" for another gear. Imagine "Barbie" (not our pal here), finding 3rd, in a 6 speed, while farding on the PCH...........

I'd say with improvements to auto trans. it is becoming more common for the 4, or more, speeds there. And, the torque converter, sort of helps split gears, if set up right.

[Ugly Dougly]

Remember where most of this legislation comes from.

The Kremlin?

[motskyroonmatick]

Damn I wish my box truck had a 6 speed. The newer manuals do. Running down to the burn with my foot on the floor 1/2 the time does suck up the fuel. I'd do an axle swap to get a two speed in there but I don't have the funds --- So I will just buy more fuel.

[Ugly Dougly]

If you put a GEO-Metro engine in an Opel sports car with 60 psi tyres, you could have it all.

The GT? Now, that would be sexy. My Car Czar would approve.

[gyre]

Remember where most of this legislation comes from.

The Kremlin?

Dense cities, where hybrids work.

[gyre]

I'm not saying data from that speed isn't valid or useful, just that that particular speed isn't significant in and of itself.
Many think there is some magic barrier at 60 mph and the government started many of these myths with the promotion of the brainless 55 mph interstate limit.
It is a much more complex issue.

I knew a doctor, who you would expect to have some science background, who was convinced all car's mileage went to hell at 55 mph.
He had no idea why, but that made no difference, because "everybody knew that".

[gyre]

60 MPH is a "significant number" because that's the speed you're allowed to drive in and around most populated areas, so it's the speed lots of us are concerned with.
Recycling by driving our older cars that already exist has a lot of merit.
Trucks can really suck to drive around empty because of their gearing! My one-ton has 4:10 gears, like almost all of them, and no overdrive. It gets a lot shittier mileage than it needs to because it spins it's large displacement engine at unnecessarily high RPM, but when loaded heavy (truck/camper/trailer combo for BM trip totals 22,000 pounds) it needs those low gears.

What I don't understand is why the hell haven't they just made transmissions with a few more gears and hell of a lot wider range?
This amazingly brilliant stroke of genius has finally been creeping into production vehicles after about a hundred years of making them with a super narrow operating range, forcing people to choose rearend gears that work for only some of what they need.

Exactly my point.
In your case 22,000 pounds is the intended use so a 4:10 can be correct depending on the engine.

Many folks I know are having good luck with the two speed add-on cases, but they are not cheap.

[gyre]

Here's a thought.
In a box truck, which is pretty much aerodynamic apocalypse to start with, how does the significance of air drag compare to weight with a load?

I would expect an empty box truck to lose mileage past 45 mph due to drag.
If the same truck is fully loaded, I would expect mileage to decline with speed, but be a smaller percentage of the total consumption, compared to the weight and increased rolling and drivetrain resistance.

Any thoughts as to how these two situations compare?
Is a higher speed more justifiable economically with a fully loaded truck (if achievable at all) ?

[Ugly Dougly]

Remember where most of this legislation comes from.

The Kremlin?

Dense cities, where hybrids work.

Okay, then, I'm no country bumpkin.

[gyre]

If you put a GEO-Metro engine in an Opel sports car with 60 psi tyres, you could have it all.

The GT? Now, that would be sexy. My Car Czar would approve.

I think there is a new hot hatchback with the diesel coming in now.

You may want to check out the very slippery kit cars many have built into hypermilers.
The Manta Can Am always got at least 25 mpg with the worst V8 setups.
A car like that needs almost no power to cruise.
The limit is on what kind of clutch is useful and if you want ac.
AC often needs more power at 55 mph (or 75) than the car needs to overcome resistance.

If you're willing to spend money on a Prius, you have a lot of choices and could find something very nice turnkey.
Even a decent, but prosaic, engine will kickass in a light, slippery body.

[littleflower]

I am going to be buying a Prius early this year. Any suggestions?

Should I get it painted green, or would that just cause more pollution?

[gyre]

[Captain Goddammit]

The problem with installing a two-speed rear end or an add-on overdrive or a newer, stock overdrive transmission is that the math doesn't work out unless you drive it a LOT.
I'd love to put an O.D. in my truck and I have the ability to do it, but it would only get me a few more MPG. The difference in cost to operate at maybe 12 MPG vs. 9 MPG means it would take a LONG time to recover the thousands of $$ I spent on the swap.
If it's worth it because you want the higher cruising speed an O.D. will give, that's different.
A newer diesel dually, with O.D. to boot, would get a LOT better mileage than my gas-engine truck- but again, the number of miles I'd have to drive it to recoup the buy-in means it's still cheaper to keep the '86 I have.

[motskyroonmatick]

The problem with installing a two-speed rear end or an add-on overdrive or a newer, stock overdrive transmission is that the math doesn't work out unless you drive it a LOT.
I'd love to put an O.D. in my truck and I have the ability to do it, but it would only get me a few more MPG. The difference in cost to operate at maybe 12 MPG vs. 9 MPG means it would take a LONG time to recover the thousands of $$ I spent on the swap.
If it's worth it because you want the higher cruising speed an O.D. will give, that's different.
A newer diesel dually, with O.D. to boot, would get a LOT better mileage than my gas-engine truck- but again, the number of miles I'd have to drive it to recoup the buy-in means it's still cheaper to keep the '86 I have.

I agree.
I did some rough calculations on improved fuel economy by installing an air deflector above the cab of my box truck and it came out to be 20 thousand miles to pay it off in fuel savings. If I were running a fleet I would have them on every truck but my 4 thousand miles a year is not going to cut it. This was a used price for the air deflector.....

[can't sit still]

motskyroonmatick, there are a lot of tractors being retired. I got a roof deflector for free and put it on a Misubishi Van,,, works good.

I changed my camper over to 3.54 front and rear. Cruises nice. Dunno about ROI. I also bought some 8-19.5 tires for the Mitsu. They're 33 inches tall on 8 lug wheels.... also go on the big six lug.

[Captain Goddammit]

Hey, since the title of this thread is "How Fuel Efficient Is Your Car"...
I have a friend who bought a little blue convertible Smart car. She claims to be getting 50+ MPG, and I know she drives it with a lead foot. I read a bunch about those things and no one else seems to report better than 40-ish MPG.

Anyone have a Smart, or have some first-hand with one? What do you really get?

[gyre]

There are several models.
Maybe she has a different drivetrain?

[Captain Goddammit]

They claim it's "the Mercedes engine model" (is there a non-Mercedes one?) with the turbo.

[gyre]

The 2009 Smart Passion comes with a new Mitsubishi three-cylinder engine in three versions, delivering 61 hp, 70 hp, and 84 hp respectively, or, in the case of the Brabus, 101 horsepower. The U.S only gets the 70 hp version. It has a DOHC 12-valve, inline-3 aluminum block and head, port fuel injection. The car has a five-speed transmission built by Getrag.
Production on the 2009 Smart Fortwo is done at the Smartville, eco-friendly plant in Hambach, France and the base cost for the 2009 Smart increased by $400.

Engineering:

* Engine Type: In-Line 3-Cylinder
* Engine Block/Cylinder Head: Aluminum-Alloy
* Displacement (l): 1.0
* Horsepower @ rpm (SAE net, Rev 8/04): 70 HP @ 5,800 rpm
* Torque (lb.-ft. @ rpm): 68 lb.-ft. @ 4,500 rpm
* Bore and Stroke (in): 2.83 x 3.22
* Compression Ratio: 10.0:1
* Valve train: 4-valve per cyl. - SOHC
* Electronic Multi-Point Fuel Injection
* Rear-wheel Drive
* CARB Emissions Rating: ULEV-2
* Federal Emissions: Tier II/Bin5
* Direct Ignition System with Immobilizer

Transmissions: 5-Speed Automated Manual

Could it be the Brabus Mercedes version?
http://www.smartcarofamerica.com/smart_ ... rt_brabus/

I find a LOT of variants ranging from mild hybrid to full electric.
Most aren't imported, but they might have one anyway.
All euro models are mild hybrid.

People used to bring in models from canada.
I don't know how those differ.

It's certainly possible with a higher compression engine.
My italian coupe had peak efficiency at 5000 rpm.
I always pegged the tach when shifting and never got under 22 mpg city.
I once averaged 45 mpg at 85 mph through the Smoky Mountains.
I got worse mileage at 55 than at 75, due to the engine tuning.
Lower drag than it looked and lightweight.
And specific efficiency is best at highest load always.
(That doesn't always equate to best mileage.)

You also have to ask how mileage was checked and for how long.
It takes a while to average out things.

Bear in mind that full throttle is the most efficient mode, so the loss is only when stopping prematurely or not lifting soon enough.
A looser engine has less friction too, so engines vary.

They estimate 40 mpg for the average cars.
Fifty is possible, but will vary, as with any car.
A turbo is more efficient, in theory, but it all depends, as you know.

These cars are tuned for premium, but most people won't use it and lose a lot that way.

I found versions with only 44 hp and very small engines

http://www.smartcarofamerica.com/
http://en.wikipedia.org/wiki/Smart_%28automobile%29

* Smart, previously called Smart GmbH, one of the car brands of Daimler AG, manufactures microcars and superminis with its head office in Böblingen, Germany, and is being produced in France.
* It is being promoted as the "smart" brand, projecting "compact" and "forward thinking."
* A sports type Smart Roadster, which is a limited version of 2000 concept Smart Crosstown and a supermini Smart Forfour was also made available to the public. Although they have been discontinued, they also plan to promote a Brazilian-made ForFour and a Mercedes smart car C-class called Formore.
* Other smart cars available are: Smart City-Coupé & City-Cabrio, Smart Crossblade, Smart City-Coupé & City-Cabri, Smart Roadster, Smart Forfour, Smart Brabus, Smart Fortwo, Smart Fortwo EV (also known as ED), Smart K (which went for commercial production and made available to the public only in Japan).
* Daimler Chrysler was presented to the public as an electric version of the Smart Car during the British Motor Show in July 2006.

[gyre]

If this info is true, it should certainly get better mileage.



This is the original 2005 Smart Car Passion Coupe imported from Europe with the Mercedes turbocharged 3-cylinder 0.7-liter 61hp engine. It is fully equipped with the 6-speed automatic transmission with the manual option, and many other options and safety features you would find on any modern vehicle. The Euro Smart Car can achieve fuel efficiency of 50+ mpg a huge increase over the American version. It also makes an earth-friendly lifestyle statement in a progressive looking car that retains the original design that is on display in the Museum of Modern Art in NYC.

http://www.vehiclemart.com/en_us/GreenC ... nit=241426

[Captain Goddammit]

a progressive looking car that retains the original design that is on display in the Museum of Modern Art in NYC.

Oh freekin' jeezus christ, they really have a goddamm Smart on display there? The Smart is one of the dorkiest-looking automobiles ever! I guess beauty is in the eye of the beerholder. I mean, it's just what you need when you only have 8 feet to park in... but art?

Here's a new question: how many cars can you name that are dorkier-looking than a Smart?

[gyre]

http://jalopnik.com/photogallery/MonkeyAztek/1000262812






















Ready for burning man
Covered in painter's tape

[gyre]

All I can really say about the smart car, is that they look better in person.


I think this would be the ideal burning man car.

[gyre]

Low gas use?