LOL! As if acetone gonna save the world and provide out-of-this-world octane boosting effect.
Either you've been spending too much of your time surfing the internet on this said subject matter (and been brainwashed into believing that), or just falling into hearsay......
2 counterpoints here:
(1)even if Acetone can be used to boost octane points, chances are, you need to add a large amount of it in order to bring your full tank of automotive gas up several points...and given the current price (just regular retail, nothing fancy)of Acetone, you'll have to spend a whole lot of mullahs in order to achieve the same results as compared to pump gas of the same octane rating, which most likely turned out to be much cheaper than you playing chemist.
(2) Nyquist is correct that too much of Acetone will melt your plastic components inside your fuel system, or even attack various elastomeric components such as fuel-line o-rings, gaskets, etc. that would otherwise be fuel-resistant...
Lastly: do you know that Acetone is such as strong solvent that it can use for dissolving otherwise hardened epoxy?
please do so at your own discretion
Q.