To think that the most efficient gas powered auto in the world is Jap built and only gets 40MPG, I have a hard time beliving that a carburator could ever duplicate that. A carb pretty much leaks gas into the air that passes through it and then gets into the cylinders and burns. Modern engines spray a mist of gas into the cylinder directly, very efficient.

A certain amount of power is needed to do work. A certain amount of fuel is required to make that power. One can only squeeze so much power out of a given amount of gasoline. At 250MPG a drop of gas would have to last for what 5-10 seconds? I'm thinking that is somewhat unlikely. Someone with more time needs to calculate how many drops are in a gallon. Really I need to know.

 

And how do you know that car got 50 mpg? Or under what circumstance? If there were some 'super carb' that really could double the efficiency of the engine, they would be in cars. Especially now that some automakers are in a serious trouble.

That's pretty much irrelevant. Gasoline may have 20% or 30% less energy today, but can't posibly be a 3x- 4x difference

 

Nope. Check out this link: http://autos.msn.com/research/vip/Sp...ivic&trimid=-1
and scroll down a bit and see what's there for the CRX HF. 50 city / 56 highway using a 1.5l 62 HP engine. Also compare it to the other Civics -- they're generally in the low to high 30's.

In any case, to get high mpg there are 2 basic approaches:
a) decrease losses (mostly frictional and air drag) -- i.e. have smaller, lightweight cars with more aerodynamic body
b) increrase the efficiency of the engine

 

VW has a so-called 1L prototype car, it made it's debut a few years ago.

It will travel 100km on 1L of fuel...that's 285 mpg.

http://www.volkswagen.co.uk/new_devs/one_litre

Super-light, tiny engine, great aerodynamics...and won't meet crash test standards for most of the Western world. But it is possible, so long as you re-think what your ideal car is.

FWIW, the 1996 Civic HX I wish i still owned was rated at 39/45. And it was a "normal" car. Too bad I didn't get thousands of dollars in subsidies for buying it.

 

Ahem, I worked for a government contractor too and know all kinds of classified stuff also... I guess that means I know my stuff and I am no phony I have also been hearing these fables since the late 60's early 70's. Some of those stories at that time were supposedly 20 years old...

Like pronstar mentioned, the super efficient cars are tiny things, going 20-30 MPH constant speeds, built like a bicycle, covered with an eggshell, driven with a single 120# driver, and are totally inadequate to drive in real life.

If you want high efficiency get a moped and drive 30MPH and you are still limited on driver weight and cargo.

 

Well, there are some high mileage vehicles. I think the Smart gets around the high 60's , maybe more, mpg (Canadian).

How does it do it? 800 cc turbo diesel which puts out about 48 hp. Pushing 1500 lbs or so of aerodynamic automobile, with a 6 speed transmission.

So it's here, isn't it, no matter what the physicists in the crowd say. No it's not 200 or even 100 mpg, but 68 mpg +, ain't bad, is it? Pretty good for a start.

As technology evolves, I predict there will continue to be tremendous engineering advances that will pave the way, for ever more efficient vehicles.

Part of the problem is mindset. Europeans have a great mindset for regarding smaller, more efficient vehicles as every day transportation.

But many of us are different. Like me. I still prefer the cars of the '60s, available with 396/350 hp engines or 428/345 hp V8s. I like the sound, the shove in the back when you mash the pedal. I like V8s plain and simple.

But, those days are pretty well gone and we have to accept the new world order, which BTW, was not originally a stolen and mis-used phrase used by the WWF. But that's a different topic.

A 2 seater. Look around when your in bumper to bumper. How many people drive alone, to work. Most.

Smarts are getting quite common in my city. Lot's of people buy them as second vehicles and keep bigger vehicles like vans, as family vehicles and highway cars. Keeps fuel costs down. You can park your bigger vehicle, and only drive it when you need to drive it.

For city driving the Smart has an appeal.

Some will respond that they don't want to be in a sardine can in an accident. Crash tests in Europe reveal that the Smart's cage structure does not too badly in protecting people.

If you hit a Mack truck, Cement mixer it won't really matter much whether or not your in a Smart, or a Excursion. Your still going to get creamed.

The guy in the Mack will wonder if he hit a speed bump too fast. There's always something bigger than what you drive.

It's the food chain.

 

No it is not here. It still isn't even close to a "magic" carb that can be installed on an every day vehicle to get 200MPG or even 50MPG. Such things are fairy tales. We will see more high efficiency vehicles if people buy them but they have nothing to do with magic carbs or conspiracy theories. High efficiency vehicles are based on sound physics and engineering applied to vehicle design allowing for manufacturability and the market for such vehicles.

 

and scroll down a bit and see what's there for the CRX HF. 50 city / 56 highway using a 1.5l 62 HP engine. Also compare it to the other Civics -- they're generally in the low to high 30's.

uh huh. The rating is nice. However *as recently reported all over the news* these ratings are made in a lab under ideal conditions. Real world numbers are not so good. Really. That is a really good number though.
So lets suppose that the most efficient gas auto made {new cars only}{mass production cars only}{and sold in the US only} gets 50 MPG. *which I doubt* that would only re-enforce what I was saying about a carb. not being able to do what fuel injection can.

LESMORE49: I'm right there with you on the classic cars with bigblocks. I think my 460 powered mustang gets 6-7 MPG.

 

Aurgathor, I am certainly not the one who understands what his dad was talking about, nor much of the physics/chemistry brought here by others ... but I will try to explain a little more about what his dad said had changed in the gas. It wasn't just the amount of energy per unit of measure, but more importantly the ability to the gasoline to transfer its energy during a burn cycle. If you take the 25% efficiency mentioned earlier (I don't know how accurate that number is, but just for kicks ...) of gasoline burned in engine cylinders, then there is a LOT of room for improvement. What if the "old type" gas burned 80% efficient (which is less efficient than my furnace can burn diesel)? That would be 320% better energy transfer and the engine would experience 3.2 times more energy per drop! So my 1989 Honda civic used to get 35 mpg on average ... 35mpg x 3.2 = 112mpg
Now please understand, I'm just throwing out numbers here and again I don't know anything about the physics/chemistry; and I suppose that we may not even be able to make comparisons like I just made, but come on! 25% efficient gasoline? We can't do better than that? It seems to me that carbuation is probably a better solution than fuel injection: the reason is that in fuel-inj. you rely strictly on the ability of the injectors to atomize the gas almost instantaneously before ingition whereas in carburation, you can utilize a series of mechanisms which facilitate the gases own ability to atomize over a longer period of time/distance before ignition, and of course, the more volitile the gas, the better. So I should think you could create several stages of the operation to improve efficiency rather than a one shot deal with the spray-mist. If I remember right, the wonderful thing about the old gas was the particle size of the atomized gas. It was much, MUCH smaller than we can acheive with modern conventional gas.
After looking into building a waste-oil burner for my furnace, it surprizes me that the actual pressures in the fuel injection ports in auto is so low, I would think they could do more just with that one variable. Like I said, I don't know much about this stuff, I am interested because it cost my pocket tons! And, yes I do know my friend's car got 50mpg.

 

I think the SmartCar is very limited in how fast it goes as well.

I doubt that high mpg will mean much when people are limited to 45 mph in the US. It takes alot of energy to go fast and even more energy for a heavy vehicle than a lighter vehicle. Also engines tend to run more fuel than is needed to burn in engines in order to keep them from getting too hot. EGR was introduced when engineers started leaning the engines closer to stiochiometric fuel to air ratios to control excessive heat produced in the combustion of hydrocarbon fuels. If one were to make the stiochiometric fuel air ratios balance so that the amount of fuel put into the engine equals the air you would have to cool the engine some how or suffer melt down of aluminum parts within that engine. I think the melting point of aluminum is little over 700 degrees C and the combustion of Hydrocarbons in a balanced stiochiometric burn is well over 1000 degrees C.

Thermal break down of your engine would probably irritate you more than the MPG you would get. You would be measure engines per mile more than miles per gallon.

 

PChiders,

It is not the gasoline that is 25 percent efficient, its the the engine itself. All the gasoline is burned, otherwise there would be raw fuel spewing out of the tailpipe. Without a catylitic converter, a modern engine still leaves less than 100ppm hydrocarbons in the exhaust stream. That means that 99.99 percent of the fuel is burned. The wasted energy is split between the heat content of exaust gasses, which a turbo can reclaim a few percent, and the rest goes into the engine metal to the coolant, oil and outside air.

Jim

 

Found this web site that shows the patents that Pogue obtained for his carburator. There was a claim that one could certainly use this carburator but required detuning the motor and the 0-30mph time was 10 minutes.

http://www.rexresearch.com/pogue/1pogue.htm

 

les, I don't think those days are entirely gone. Even in Europe, there are enthusiast who love the older muscle cars. While they may not be able to drive them evrey day, I think we will always be able to enjoy them on a more limited basis.

The Smart is definitely fun. I've had the cnahce to drive them. They aren't fast by any means, but it is a rewarding drive...in an entirely different way than a musclecar, of course.

 

http://www.rexresearch.com/index.htm

I read all about the carb. at the above link, duh! So silly of me! The guy's lawnmower ran for a week on a pint of gasoline! And his car only got 200 MPG. I guess it must work then!



Patrick Davies, 72, from St Austell, had owned the tool box for 40 years but only recently decided to clean it out. As well as drawings of the carburettor, the envelope contained two pages of plans, three test reports and six pages of notes written by Pogue.

They included a report of a test that Pogue had done on his lawnmower, which showed that he had managed to make the engine run for seven days on a quart (just under a litre) of petrol. The documents also described how the machine worked by turning petrol into a vapour before it entered the cylinder chamber, reducing the amount of fuel needed for combustion.

 

I should have put supposed patent. If one looked at the drawings for this carburator it looked to be massively complex for a one barrel carburator.