I have been running Optimal ie. Opti-2 for 20 years. I use it in weedeaters, chainsaws, blowers, heck I even add it to the gas I put in my 69 Ford F-250 Explorer, 390; 1974 F-350 6 Cyl ; My 77 F-350 302. Opti-2 coats the cylinder linings. I believe it helps preserve unleaded gas to...