Have been running Opti-2 in my 4 cycle equipment. I was concerned at first because I use the US Gallon vs Imperial gallon, so my ratio is more like 72:1 instead of 100:1. I thought it would be too rich a mixture to run in my 4 cycle snowblower. So far it is super… really fast starts and no smoke. I can’t wait to inspect the plug once the season is over. If it is anything like my 2 cycle blower, the plug will be clean and like new. I’m sure tha the Opti-2 will provide upper cylinder lubrication and hence, longevity, the same way diesel fuel lubricates as it burns. Thanks, Brad for your assistance. One gas can makes life so easy!!