I tried Acetone in different ratio's on my 2 stroke scooter, 4 stroke scooter, V8 truck and my ti. NOTHING!! It is BOGUS. I bet Acetone sales went up when this claim made the internet. Do not try it unless you have time to waste.
Change your catalytic converter if it's never been changed. Made a HUGE difference for me... used to get about 28.5 mpg with mostly highway driving. Now im about 33.5 mpg.