[Editor's note: In recent tests, I got only a moderate, 5%-8% (if that much), improvement due to acetone. Also, click the above Acetone & Gasoline link to see the most recent posts on the topic.]
Mythbusters finally tackled the issue and tested car performance with acetone mixed with gasoline. Was the mileage improvement touted by Louis Lapointe confirmed? Plausible? No. And no. Totally busted.
They didn’t test the full range of mixtures, but said they used about a 500:1 gasoline:acetone ratio. That’s about 2.56 fluid ounces per 10 gallons.
Just like the engineers at Kettering University, no improvement due to acetone was found. In fact, it looked as though mileage was decreased in all four of their scenarios (2 speeds times 2 cars) on the dyno.
UPDATE: whoops! I thought tonight’s episode was new. I was wrong, according to Wikipedia it aired on May 10, 2006. And crazy ol’ LaPointe defends himself in his FAQ (seriously, read it and decide for yourself that the guy is nuts):
Did you know that MythBusters says acetone reduces mileage? I heard that. Of course it is false. The whole purpose of asking people to buy a ScanGauge is to find out the Truth for themselves. MythBusters created a myth rather than busted one. Perhaps they were paid to promote controversy with unscrupulous propaganda. Perhaps to create controversy to gain audience. But it looks like acetone was hurting somebody’s profits. Nobody pays me anything. I get my monthly SS and live off that, including what I spend on testing gasoline which is damned expensive. There are lots of things I could do with the money than waste it on a lie or keep searching for ways to improve mileage. Why do I do this? I do it for the public–for you folks, out of my good heart. The liars are not hurting me because I do not depend on them. They hurt the public with their unfounded and/or inaccurate opinions. Get a ScanGauge, people.
Is it possible MythBusters deliberately faked bad results with acetone? Possible for a simple reason. Their conclusion is out to lunch. This additive works in such tiny amounts that it could cost the industry billions in lost sales–keeping that money in your pockets. Here are just a few ways to rig a test for failure. Bad plug wires or bad spark plugs. Bad acetone with water or benzoate. Bad fuel mixture. Bad ignition timing and/or computer settings. An engine in poor condition. That is why I suggest you keep your engine and car in top condition when you test fuels with acetone, GP-7, neohexane or xylene. When I first started examining acetone for MPG back in the 50s, I found I could not depend on test results unless the engine was in excellent condition. Over the years I eventually found the parts that give best mileage. 50+ years of testing means I am a very stupid individual or lying like a rug to maintain this position on acetone and other mileage tips. Both my ScanGauges must be lying too. Be aware there are hundreds of people seriously testing fuels out there–who must be liars also. The Truth always comes out. Always. The method of testing I use is repeated over and over to avoid errors. I never test just once because gasoline changes. Everything changes. I guess I have tested acetone thousands of times by many different ways. I wonder if the same people who faked bad test results with acetone have also praised ethanol. Plus the good acetone comes from Klean-Strip or 100-percent pure from Sally Beauty Supply, that is worldwide.
Way back when I addressed this, I speculated that the guy was making money by selling ScanGuages, because half of his website is about buying one so you can do yourself the favor of testing your car.
Being credible shows up nowhere on the guy’s site. Like I said, his “data” exist on a level consistent with high schoolers and not with anyone with credible technical training. And he doesn’t bother to say something like “hey, buy any equipment you believe in and test for yourself.” It’s always ScanGuage ScanGuage ScanGuage!
The second paragraph from his FAQ is hilarious, too. Most of his defenders use really crapped out cars to test acetone before swearing that acetone works. Now he’s saying that your car must be in top working order for it to work. Keeping your car in top working order is the recommendation made by everyone who knows anything about cars. It’s also exactly what the oil and auto industries recommend (remember, according to LaPointe, these industries are doing everything they can to keep mileage down). But most of the people who would be into acetone are the people who do not want to spend money on repairs, upkeep, etc. (I also like how he capitalizes “truth.”)
Louis may be an honest guy, but if that’s the case he’s apparently a horrible scientist. Or he is a flat out liar. Either way, I find zero reason to believe the guy.
UPDATE 2 – 6/18/2007: LaPointe is right about one thing. Fuel mileage is highly variable and dependent upon conditions. So it is accurate to say “gasoline changes. Everything changes,” and that extensive testing must be done to verify something. And really, it should be done in the laboratory. If not done in the lab, the testing must start with an extensive testing of baseline conditions. That means, for the average driver, they must record months of mileage results and conditions to start with. Otherwise, without a solid baseline, any quantitative comparison is fairly useless. I venture to guess that the vast majority of people who report on their tests — myself included — have not sufficiently established a set of accurate baseline data.
To add to that, Chevron
has had a very useful page about calculating mileage and what factors can affect your mileage and by how much. [Edit 2010-01-24: The Chevron page has been changed dramatically since I first linked to it, and is now much less useful.]
As an extra example, another episode of Mythbusters tested fuel mileage of a car at varying distances behind a semi. The results varied from about 32 mpg up to 44 mpg. Same car, same driver, same gas, same day, the distance behind the truck had a huge impact on mileage.
Links of interest:
- Engineers at Kettering University were unable to find increased mileage due to acetone..
- Acetone probably can’t improve the surface tension of gasoline.
- Oil companies make most acetone.
UPDATE 3 – 6/18/2008: Just a few thoughts/comments from my end:
- The above link to a Chevron page still works, but the page has changed significantly, which is a shame.
- If you’re going to leave a comment, try to be smart about it. This means that at least a little bit of proofreading is a good idea. It also means that if you’re going to post your results from your own testing, describe things like how you established your baseline and what your baseline was and then go forward in describing the with-acetone results. Honestly, I’m getting a little tired of the dreadfully stupid comments being left these days. They are so bad that I can’t tell if they’re supposed to be serious or funny.