What galls me is I have an old tractor which uses 93 octane gas and I can’t find it anywhere. Since I use it off road I cannot find any off road gas(untaxed) either.
My little tractor is diesel and there’s no one around here that sells off road diesel. Not worried abut it because it’s a sub-compact with 3 cyl engine that sips fuel. I am half thinking about getting an old 82 to mid 90s Mercedes car with the 4 cyl diesel and running 85/15 WMO/Gas. WMO = Waste Motor Oil. WMO/Gas works better than waste veggie oil.
Requires some equipment including a centrifuge though. https://usfiltermaxx.com/en/content/9-make-black-diesel
Used motor oil can be had for free and if gas went to $10/gal, it would only be $1.50/gal to make black diesel. There were guys back when Obama was in and gas was about the same price as now and they were running it in their Powerstrokes
If it was $10/gal, it wouldn’t take too long for the ROI at $8.50/gal savings to pay for a $2500 centrifuge. 300 gallons or so. 15 tanks fulls for 20 gallon tank.
At the current $5/gal it would take 714 gallons or approx 36 tank fulls. Plus you need more than just the centrifuge. Pre-filters, tanks, jugs etc. Call it $3500-4000 which would probably take a couple of years for ROI.