I use acetone in small amounts 1-3 oz per 10 gallons of gas. It's cheap in bulk and does increase MPG. Another thing it is in expensive fuel additives. I have read the patents granted for it's use in improving fuel MPG as an additive. Just search patents gasoline acetone mpg, or patent gasoline additive acetone, anyway that's how I discovered it when I looked at hundreds of other gas saving systems patents. There is like over 400 gas saving patents. Acetone cleaned my fuel tank and I had to change the clogged fuel filter soon after I started using it. But in the small amounts no problems, I have been running it a year.