... try running 87 octane for a tank then run 91... you will get alot better mileage with the 91 octane. that is why some people don't mind buying 91 all the time. It evens itself out with better gas mileage. My dad was the one i got this from when he ran 87 and 91 in all of our vehicles and found a pretty significant increase in gas mileage. I'd rather just put 91 in all the time then run acetone through my system. If you read far enough into the article it reveals that all its doing is changing the octane. But acetone is some bad stuff for any king of plastic, gasket, or rubber. 91 octane however isn't.
If i still had my 180,000 mile stock 350 in there i wouldn't do it because acetone will eat seals and gaskets and pretty much anything that gets in its way besides metal. I sure as hell won't put it in my 0 mile 355. Maybe i'll get my bro to try it in his tired 4.3.