I've certainly never heard of this so I'm just going to give opinion in response.
Ok, so you make it sound plausible but my first instinct is that water doesn't burn, how can that help. Also introducing water into the system makes me wonder if there will always be some residual left somewhere in the exhaust system leaving it to corrode sooner than later.
There's water in the exhaust system already. For each gallon of fuel you combust, the engine forms approximately a gallon of water that's then chucked out the exhaust. Unfortunately, the water is usually formed late in the combustion phase from the hydrogen in the fuel and the oxygen in the air, and thus doesn't contribute much to engine power or fuel efficiency.
The water doesn't combust, it's merely there as a superior expansion medium to add to cylinder pressure. A side benefit is that it quenches combustion temperatures, so less NOx is created. It also acts as internal cooling, so less radiator-based cooling is required.
The water is there to help increase cylinder pressure but why? Is this because with better pressure you use less gas and therein lies the better efficiency?
Yes, the phase-change of water to steam is a better expansion medium than air. Not only does it expand more than air for any given temperature delta (water flashing to steam vs. air expanding due to temperature increase), but it also helps to quench and moderate the high combustion temperatures that cause NOx creation.
If I was to move forward with something like this I guess I would first make up the mixture (shaken, not stirred). Sorry, Bond just jumped into my head. Undiagnosed ADD popping in there. Anyways, mix it up and let it set for a month and then scientifically (with your eyeball) look for separation of the chemicals. From there I may drop a complete new mixture into an old lawn mower or something like that. Mow your yard 5 times with regular gas and measure how much you use. Try the "mixture" for 5 mowings and see how much you use. I'd probably put in a new spark plug each time for something additional to look at at the end of each 5 mow session. Maybe even before and after pictures of the cylinder and head for each. Record the time the mower was running for each session as additional data. Gather as much info as you can and in the end, make some decision about what has happened.
Where did you hear about this? Do you have (credible) links to research? I guess the gas companies are already adding water to gas cause that's what separates over the winter if you don't drain your carb right?
I was actually researching additives, came across acetone, and was wondering why some people experienced great gains, some experienced no gain, and some experienced losses... especially when using E10. In doing further research, Sir Harry Ricardo and his Racing Discol fuels came up, and it dawned on me that it's not the acetone alone that's causing an increase in power and fuel efficiency, it's acetone's miscibility with ethanol, the components of gasoline
and water that was allowing any water in the tank to be used as an expansion medium in-cylinder. It also lowers the surface tension of fuel droplets, thus the droplets are smaller, thus providing more surface area per droplet, thus allowing them to evaporate more quickly.
You have to be careful when adding water, it can cause a tremendous increase of cylinder pressure. Thus the increase in power some have seen when adding acetone. It must have scavenged any water in the tank and sent it along with the fuel. Those same people later saw their gains in power and fuel efficiency mysteriously evaporate, going back to what they normally were. Most attributed this to their ECU adjusting to the fuel mix, but I suspect it's just that all the in-tank water was consumed. Relative humidity of the intake air may play some part, as well... humidity-laden air would have just enough time to mix the water with the ethanol and acetone before intake. So those who saw fuel efficiency and power gains on wet days, only to see those gains go away on other days, may have experienced this.
Here's some info on Ricardo's RD1 and RD2:
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http://www.vintagenorton.com/2012/07/benzole-alcohol-fuel-and-sir-harry.htmlWriting in 1992, the late Dr. Joe Bayley told me that alcohol was used at Brooklands prior to the Great War, both as a fuel and as an additive. But he went on to say that it was towards the end of the 1922 season that Discol really became popular.
RD1 (RD= Racing Discol) was made up of 80% Ethanol, 10% acetone and 10% water. It was mainly used for short races. RD2 was 80% Ethanol, 10% Benzole and 10% Acetone - used mainly for longer races - while PMS2 (Pratt’s Motor Spirit), which JB considered probably the best of the three, was a simple mixture of 80% Ethanol and 20% Benzole.
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Benzole (aka Benzol) (a mixture of benzene, xylene and toluene, usually) is a carcinogen and the reformulated gasoline mixtures are attempts to remove or minimize these constituents from gasoline.
I had a neighbor tell me all about adding acetone to his tank for better gas mileage several years ago. Never had the courage to try it on one of my cars (expensive experiment if it goes wrong). I'm not sure if he ever went through with it either and he's a mechanic who can tear down and diagonose pretty much any combustible engine. Me not so much.
I'm going to do much the same as you suggest... mix up a batch in a glass container and let it sit for a while to ensure nothing settles out. Given the miscibility of acetone in water, ethanol and the components of gasoline, it should all stay homogeneous, unless the mixture ratios are way off. Then I'll give it a try in the FrankenYager if all goes well with the glass container test.
If worse comes to worst, I'll be draining the tank and refilling with regular gas. I don't expect it'll do any actual damage to the engine.
