Gas Vaporizer: Fact or fiction?

[Mateo]

In general I'm a highly skeptical person.

Recently I have decided to do my part to consume less gasoline. I bought an old 1989 Civic which gets 35+ mpg. Compared to my old Jeep Wrangler, this is wonderful.

So I started reading on the internet of other ways to increase my mileage. I stumbled across a website selling a "gas vaporizer." In short, it is a small device you attach to your gas line that will vaporize your gas, essentially making it more combustable.

To a layman like myself (I can't even change my own oil) their explanation makes sense, but I still am skeptical. Something tells me that if all it took to increase gas mileage was to add a $100 device to each car auto makers would have done this a while ago.

So, are there any mechanical experts out there who can tell me the science of WHY this is stupid? While you're at it, how can I increase my mileage?

Mateo

[Mr. Skinny]

Carburators or fuel injectors are already provided to vaporize your fuel. I'm not sure what this add on gizmo is supposed to do in addition to that.

Do you have a link to the product?

[Mateo]

Originally posted by Mr. Skinny
Carburators or fuel injectors are already provided to vaporize your fuel. I'm not sure what this add on gizmo is supposed to do in addition to that.

Do you have a link to the product?

Yes, here it is:

http://www.increase-gas-mileage.com/

The URL should be enough to drive me away, but now I'm interested in knowing WHY it's not fact.

[Mr. Skinny]

Looks like B.S. to me, but there's really not enough information to state that definitively.

This quote
In contrast, your engine needs vaporized gas for proper combustion - this means that you are presently wasting gas, because only a portion is being vaporized - the remaining liquid gas passes through your engine, sludges up your oil and finds a home in your "catalytic converter" to be broken down by the intense heat build up! Another technology to meet more arbitrary "emissions laws!"
seems like total B.S. While some liquid might get by the piston rings when the engine is totally cold, once it warms up, any liquid should instantly vaporize on the hot piston/cylinder walls.

I also don't understand how it is "installed in parallel" with the fuel line.

Let's just say I won't be buying one soon.

[Frinkiak7]

Is it just me, or do most of the components pictured on that site look like an installation kit for a freezer-mounted ice maker?

Anyway, the statement that "only about 20% of your liquid fuel is being vaporized" strikes me as being a little off. I don't expect the vaporization process to be 100% efficient, but I'd like to know where they get that 20% figure.

[TeaBag420]

This is the problem:

"This is an inefficient system because the energy from air is what is used to change the petroleum fuel from a liquid to a vapor. The energy in air is efficient for a 3 carbon chain molecule - like propane, that liquid fuel will change to a vapor readily - it's inefficient for an 8 carbon chain molecule (e.g., octane) such as gasoline."

=======
This is just wrong. The fuel is vaporized by a mechanical process.
=======

"The whole problem with poor gas mileage is that all of the liquid fuel is not being converted to a "gaseous" state - vaporized - by carburetor's and fuel injection systems. In reality only about 20% of your liquid fuel is being vaporized - the rest is being wasted. This sludges up your engine, creates wear and tear - in fact the catalytic converter was added several years ago to burn off this wasted fuel using a platinum catalyst in place of oxygen - to artificially lower emissions."

========
This part is sorta true. The second stage of a catalytic converter does take care of unburned (or incompletely burned?) fuel. But I question the 20% figure; exhaust on older cars doesn't really smell like gasoline.

And I suspect it has to do with air to fuel ratio rather than poor vaporisation of fuel.

[Bikewer]

Modern computer-controlled fuel injection systems are amazingly efficient, and gasoline is quite volatile.

Hard to imagine that some little gas-line gizmo would improve the process much.

[TjW]

You don't want your fuel vaporized.

It sounds like a good idea until you realize that you can't move molecules of fuel into the combustion chamber as a gas as easily as you can as a liquid. So it's harder to get the stoichiometric mix of fuel and air for optimum combustion when the fuel is completely vaporized.
Automotive engineers actually have spent a fair amount of time and money making fuel injectors have the optimum droplet size: Big droplets let you put in fuel more easily, small droplets have more surface area per unit mass of fuel to burn quicker.

The catalytic converter doesn't burn unburned gasoline. (Okay, it would, but it would burn out pretty quickly) It's there to burn the carbon monoxide in the exhaust down to carbon dioxide.

[Orangutan]

Something tells me that if all it took to increase gas mileage was to add a $100 device to each car auto makers would have done this a while ago.

You are well attuned to spot gimmicks already, "If it sounds too good to be true. it is."

Thier site claims an avarge of %40 saving. That would mean an extra 120miles on a tank of gas for me.
I think I'll pass.

O.
:)
Oh and welcome to the forums! :)

[rwguinn]

Originally posted by TjW
You don't want your fuel vaporized.

It sounds like a good idea until you realize that you can't move molecules of fuel into the combustion chamber as a gas as easily as you can as a liquid. So it's harder to get the stoichiometric mix of fuel and air for optimum combustion when the fuel is completely vaporized.
Automotive engineers actually have spent a fair amount of time and money making fuel injectors have the optimum droplet size: Big droplets let you put in fuel more easily, small droplets have more surface area per unit mass of fuel to burn quicker.

The catalytic converter doesn't burn unburned gasoline. (Okay, it would, but it would burn out pretty quickly) It's there to burn the carbon monoxide in the exhaust down to carbon dioxide.
anybody remember the tendency of the '55 Mercury and its ilk to "Vapor lock" during hot weather?
get a slug of vapor in the fuel line, and the vehicle quits working. You can't pump it, and the carb has no idea what to do with it if it gets there...(Excuse the anthropomorphism--but all my friends swore that that dadgummed car had a personality--and it was not a nice one)

[Mr. Skinny]

Originally posted by TjW
You don't want your fuel vaporized.

It sounds like a good idea until you realize that you can't move molecules of fuel into the combustion chamber as a gas as easily as you can as a liquid. So it's harder to get the stoichiometric mix of fuel and air for optimum combustion when the fuel is completely vaporized.
Automotive engineers actually have spent a fair amount of time and money making fuel injectors have the optimum droplet size: Big droplets let you put in fuel more easily, small droplets have more surface area per unit mass of fuel to burn quicker.

The catalytic converter doesn't burn unburned gasoline. (Okay, it would, but it would burn out pretty quickly) It's there to burn the carbon monoxide in the exhaust down to carbon dioxide.
You're right TjW. I was using the term vaporized in a very loose way. Fuel injectors spray a fairly precise cone of droplets of gas... far from being a vapor, but the web site was using that term, so I just went with it.

Thanks for clarifying.

Agree on the catalytic converter also. As I understand it, raw fuel will wear out a converter in no time, but I claim no expertise there either.

[Soapy Sam]

If 80% of the petrol injected to an engine is unburned, where is all the energy coming from?
Also , why aren't our highways a mass of igniting exhaust fumes?

Engines are engineered to burn liquid fuel effectively without preignition problems. Adding another vapouriser stage will hinder, not help.

Of course, you could try adding tetraethyl lead...

[Mr. Skinny]

Originally posted by Soapy Sam
(snip)
Of course, you could try adding tetraethyl lead...
They named the suburb next to me after Charles Kettering. He did a lot of work on leaded gasoline.

Interesting dude. Did a lot of work with refrigeration (think Frigidaire), worked on buzz bombs during world 2, auto-starter for cars (think Delco), etc.

[TeaBag420]

Originally posted by Mr. Skinny
They named the suburb next to me after Charles Kettering. He did a lot of work on leaded gasoline.

Interesting dude. Did a lot of work with refrigeration (think Frigidaire), worked on buzz bombs during world 2, auto-starter for cars (think Delco), etc.

So they named a suburb after a Nazi? Cool.
:bs:

[TeaBag420]

Originally posted by Bikewer
Modern computer-controlled fuel injection systems are amazingly efficient, and gasoline is quite volatile.

Hard to imagine that some little gas-line gizmo would improve the process much.

Pssst!!! "I lack imagination" isn't a very persuasive argument. I'm just saying.

And volatility isn't the issue here. What goes into the chamber is tiny droplets, not gas.

[TeaBag420]

Originally posted by TjW
You don't want your fuel vaporized.

It sounds like a good idea until you realize that you can't move molecules of fuel into the combustion chamber as a gas as easily as you can as a liquid. So it's harder to get the stoichiometric mix of fuel and air for optimum combustion when the fuel is completely vaporized.
Automotive engineers actually have spent a fair amount of time and money making fuel injectors have the optimum droplet size: Big droplets let you put in fuel more easily, small droplets have more surface area per unit mass of fuel to burn quicker.

The catalytic converter doesn't burn unburned gasoline. (Okay, it would, but it would burn out pretty quickly) It's there to burn the carbon monoxide in the exhaust down to carbon dioxide.

Check your facts on the multiple targets of catalytic converters.

[TeaBag420]

[CaveDave]

Just a few comments.

Some fuel does pass unburned past the piston rings into the crankcase, particularly under cold conditions (that is why thermostats and intake air preheat systems are used.) or if fuel atomization is inefficient (dirty injectors, inefficient carburetor, poor intake design, etc.). Also, droplets can stick to the cylinder wall, head, or piston, and be quenched so they exit unburned with the exhaust.

The PCV (Positive Crankcase Ventilation) system was included since the 60s to pass these vapors plus any oil mist and water vapor through the cylinders to be burned instead of venting overboard (anyone old enough to remember the oil stripe down the center of highway lanes?). This also helps the oil last longer by evacuating these contaminants before they condense into it. It appears that this gizmo passes those crankcase vapors through the fuel in the device to vaporize it and add it to the PCV stream.

In almost all cars since the mid 80s, there is a feedback system that measures the oxygen content of the exhaust stream and adjusts the fuel mixture to maintain a slight oxygen surplus which translates to almost complete combustion. Most of these systems will vary the mixture slightly lean to slightly rich many times per minute to many times per second to maintain the mixture right at the knife-edge of stoichiometry (and also for other reasons--later). On one of these engines, the extra fuel supplied by the PCV or other vapor recovery systems or by this gizmo is compensated for within limits by the feedback system.

Catalytic convertors utilize the rich-lean variation to store oxygen to oxidize carbon monoxide, soot, or any small amounts of unburned hydrocarbons into carbon dioxide and water vapor. They also reduce oxides of nitrogen into nitrogen and oxygen. Feed them too much unburned fuel (as in a misfiring cylinder) and they will glow bright red, melt the core, and plug up.

Most modern engines are quite efficient at burning the fuel almost entirely.

The easiest gas saving trick is to maintain the engine in top condition and lighten up on the old foot.

Dave

[Mateo]

Thanks everyone for the replies. In my search to make my care more gas efficient I'm sure I will encounter many of these gizmos along the way.

Oh, thanks for the great welcome to the board too :)

[Mr. Skinny]

Originally posted by TeaBag420
So they named a suburb after a Nazi? Cool.
:bs:
He wasn't a Nazi.

I mistakenly said WWII when I should have said WWI.

Take a look here (http://www.edwards.af.mil/articles98/docs_html/splash/may98/cover/early.htm) to read about his "Bug", an unmanned aerial bomb.

[tedly]

You[re going to run across a lot of tips that range from the boring and practical to the exotic and useful. 'Drive like there's an egg under your foot, slow down 'cause air resistance goes up as the square of your speed.' 'put this magnet under the crystal so the structure of the gas molecules is changed....'

This set me off:
The energy in air is efficient for a 3 carbon chain molecule - like propane, that liquid fuel will change to a vapor readily - it's inefficient for an 8 carbon chain molecule (e.g., octane) such as gasoline."

Gasoline is not a molecule, it's a sludge. It's made up of all the stuff that boils off from crude from 100deg F to ~400 F.
Octane is a chemical that is used in fuel testing because it's very resistant to 'knocking'. A mix is made up of 87% octane and IIRC heptane, anyway something that knocks like a brute. If the test fuel knocks at the same compression ratio as 87% octane then it's rated 87 octane 'motor method'.( Another method, called the 'research method' is the normal one reported on your fuel pump, and it's the reason you see ratings like 110 or 120 octane.)
That doesn't neccessarily mean there's any octane at all in the fuel. Describing gasoline as an 8 carbon molecule indicates that this is just bs-baffle, not an explanation.

[TeaBag420]

Originally posted by Mr. Skinny
He wasn't a Nazi.

I mistakenly said WWII when I should have said WWI.

Take a look here (http://www.edwards.af.mil/articles98/docs_html/splash/may98/cover/early.htm) to read about his "Bug", an unmanned aerial bomb.

As opposed to a manned bomb?

Since you originally said "buzz bomb" let me read you part of the web page you cited:

" During the Second World War, Nazi Germany's "buzz" bombs or "doodlebugs," revealed a new technology: compact axial flow turbo-jet.

After the war, the United States incorporated the German advances with the new field of electronics and came up with Teledyne Ryan Q-2.

This squat, noisy remotely piloted vehicle became the basis for a new generation of high speed targets and reconnaissance vehicles."

[Bikewer]

Hehe- the Japanese had a manned bomb. The "Baku" was a rocket-propelled bomb with rudimentary flight controls. Dropped from a "Betty" bomber, the weapon was guided to it's target by the Kamikaze pilot.

[davefoc]

We have had discussions about various gas saving gizmos before. One of the things that I learned as a result of these threads is that the EPA has tested a number of after market add on devices advertised to increase milage and has found the all to be either completely or almost completely ineffective.

The EPA has a test procedure that can be used for add on milage increasing devices. If a device was legitimate it could get an actual EPA certificatin to that effect if it successfully completed the EPA testing. At this time, I don't believe there are any devices that have.