I was cruising the web for race fuel ideas and found this. I had to comment... https://www.physicsforums.com/showthread.php?t=195647 The UOP Shadow team ran a Can-Am car in 1971 and their crew chief was a self taught engineer named Peter Bryant, a really smart guy. UOP sold unleaded fuel and back then they had no readily available unleaded racing fuel so they (UOP) had to come up with something or look a bit idiotic running someone else's gas in there cars. They came up with a mixture of 55% "isooctane" (i.e. precisely 100 octane unleaded) and 45% regular old acetone off the shelf. This made for 104 octane fuel. Peter was worried about it eating the fuel system up but they had no problems. They ran a 497cid BB Chevy producing 735bhp. I think it was 13:1 static compression ratio in the naturally aspirated car (101). Acetone most definitely works as a fuel system safe octane booster (I don't know about people safe) and if you do your home work you will find higher octane fuel will make for better fuel milage as long as the computer can take advantage of it and advance the spark timing to compensate. It won't make massive differences but it will make a difference. I'm not sure of the cost to benefit ratio though. My two bits. Side note: The Mercedes and I think AutoUnion ran a Shell fuel blend in there Grand Prix cars in the late 1930's that included about 10% acetone in the mix.