So a bit less than 1/2% acetone works as an igniter? I have heard 2% but if 1/2% works as well, then it may be worth a try on some FAI type 0% fuel for some of the larger motors I have. I like the 10% fuel rule in control line speed events too. The 1/2A class was exempt from that rule for a while, but eventually went with it anyway. They seem to thrive on the nitro, but with some higher revs they work just as good with nearly the same speeds as the high nitro.