I have used it for quite a while. I tend to add about 2oz to each tank (16.5 gallons). And I have seen a 3MPG improvement. I tracked my mileage in a another program before I found this, but I will be tracking with Fuelly shortly.
It appears that no one has remembered any thing about chemistry!
Remember that Acetone will partly dissolve Silicon, and given enough time in contact it will eventulally dissolve enough of the fuel line componets that on most older American made autos from about 1990 thru current date, as well as some imports, the vehicle will start to have fuel line problems. In some cases where the vehicle has a manual fuel pump instead of fuel injection, the Acetone will actually dissolve the Silicon diaphram of the fuel pump. Auto makers changed over from rubber fuel system parts to Silicon to avoid this very problem with the early "Gasohol", (Ethonol), fuels. The alcohol was dissolving the rubber fuel system componets, and thats why they switched to fuel systems made with Silicon componets.
To put it bluntly, using Acetone like I did in the past, is going to leave you stranded at a very inconveient time and place! By the way, I never saw any MPG increase what so ever. It was used in a 1996 Ford F150, and it was cheaper to trade it in than to fix it!
I have had a stroke, and my typing, spelling, and grammar are not very good. So go easy on me when criticing my comments. Thank you.
The reason that Ethanol decreases your mileage has little or nothing to do with surface tension, it is due to the much lower BTU (British Thermal Units) content per weight and unit volume than gasoline. A 10% Ethanol (E10) gasoline mixture drops mileage substantially due to the Ethanol's lower BTU rating (the amount of energy stored in fuel that is released in combustion). In my 2000 Acura Integra when Southern California goes to "Summer Blend" gas for Air Quality Management District rules my mileage often drops by as much as 20%. The only good news is that it recovers upon the return of "Winter Gas" 4-5 months later. The Ethanol has been added to Southern California gasoline for quite a bit longer than the rest of the nation due to the outlawing of MTBE which was used in very small quantites per gallon only to be replaced by Alcohol, I believe it was originally Methanol, in quatities of up to 15%. From tracking my mileage I could literally tell you the exact date that I got my first tank of Summer or Winter Gas in my freeway commuter.
Also, while I don't remember my chemistry as well as the previous poster does, I can tell you that Acetone is a very polar solvent and it does disolve many plastics quite effectively so I wouldn't put it in my gas tank even with the promise of added mileage. As it is we are all going to be paying the price for Alcohol in our tanks as Alcohol is attracted to water and many fuel system components in older vehicles are steel based. Add water to a steel system component and you inevitably end up with rust which will play havoc on fuel filters, not to mention injection systems, fuel rails, fuel pumps, and combustion chambers.
Finally, I believe that you can find some non alcohol gasoline for off highway vehicles. The last I checked so called racing gas formulated for non street legal motorcycles, dune buggies, ATV's and the like did not contain so called oxygenators. Also AvGas for airplanes still contains Tetra-Ethyl Lead in some mixtures like 100 LL which stands for 100 (apparent) octane Low Lead, it is also referred to as "Blue Gas" due to the blue tint that is added to the fuel after refining as a visual reference to pilots that the appropriate grade of fuel has been used to fill the aircraft. It may be difficult to find an airport fuel company that is willing to sell you gas though so I'm not sure that it would be a viable option. I used AvGas for an old outboard motor on a ski boat after California outlawed leaded gas back in the late 1980's as the soft exhaust valve seats would have been ruined by unleaded gas in short order. It was cheaper to pay the high cost of "Red Gas" which was 80/89 octane at the airport than it was to replace the valve seats in that engine.
I tried it once with my wife's minivan. I added 2 oz to her 16 gallon tank. Within a week 3 of the 4 O2 sensors had failed at $70 each to replace. Ended up costing more money in the long run. It wasn't worth a try.
It's hard to know here in Florida how much ethanol is in gas, since the gas doesn't have to contain any; it just has to have not more than 10%. Gasoline already has rather low viscosity and good vaporization characteristics. It also has a higher BTU value than acetone (which is just partially oxidized propane), so - unless you can get a really great deal on acetone, it's not worth it. Also, acetone is a VERY aggressive solvent, one I would not DARE put in my fuel system in any concentration.
Don't mess up your injectors or fuel pump trying to save a few dollars!