2 stroke oil in fuel for economy boost?
 

So I had a friend suggest running a small amount of two cycle oil in my fuel for a small mileage bump. Intrigued and glad skeptical I did a google search and apparently it’s a thing?

https://www.tundratalk.net/threads/a...nd-mpg.163858/

Thoughts? They’re talking about running it like 400:1+ in their fuel, maybe it helps lubricity of the fuel, cleans stuff, whatever? I mean, it’s an oil designed to be burnt and they do run it in rotaries…

Do a site search for 'acetone'. Here's an example post: ecomodder.com/forum: 35% gain using acetone/xylol...

I tested it years ago. Double blind test on my wife's car. Added a 16 ounce bottle to the cavernous gas tank of a 4.6L town car. It appeared to at least improve fuel economy, but not enough to cover the cost of the 2 cycle oil. I would have her run it till the fuel light turns on, dump in the 2 stroke oil and fill it up. Same for the no 2 stroke oil tanks.
I would say yes it can improve fuel economy. And it may be economical for some vehicle and engine combinations.

Naphthalene in gas also improves fuel economy but also cost of materials doesn’t cover the improvement

My limited knowledge of chemistry says they are getting the direct injection droplets modified smaller possibly by reducing surface tension. 2 stroke oil does that somewhat, more so for the aromatic volatile solvents

acetone
 

It's one of the most aggressive 'over-the-counter' solvents. You'd have to be very careful with gaskets and O-rings.
Very expensive.
CRC Manual would have it's mass Btu heating value rating.
HONDA R&D may have used it at the Indy 500 in the 1980s as a motor fuel. Really high octane-equivalency ( high-compression capability ).
Don't breathe it!
Don't get it in your skin.
It's probably a known and registered mutagenic, carcinogenic VOC.
Material Safety Data Sheet probably available online.

I had previously heard of Acetone, Xylene or other similar solvents but didn’t understand how they would help mileage and after seeing what xylene would do to a cup I didn’t want it in my fuel system. The two stroke oil (or possibly rotary premix) seems like a viable idea at no more than an ounce to 3 gallons of fuel if it helps

two-stroke oil
 

1) Scientists would say it's anecdotal.
2) There's no controlled instrumented testing.
3) No numbers.
4) No independent verification.
5) Just subjective commentary.
6) I've never seen fuel 'lubricity' issues mentioned in industry literature.
7) Detergent motor oil will clean grease off your hands. Castor oil, or something like it would not be a surfactant or solvent.
8) A two-stroke engine is lubricated by it's fuel.
9) An automotive engine already has closed, pressurized, hydrodynamic lubrication.
10) Two-stroke mixture enters the bottom-end of the engine, lubricating the big end of the crank, and piston-pin, before leaving the crankcase and entering the cylinder ports, lubricating the cylinder walls before being captured in the cylinder head. None of this occurs in a four-stroke Otto-cycle engine. And I think two-stroke Diesels were discontinued many decades ago.
11) Oil might have a higher heat content than gasoline ( diesel does ), however, at such a 'lean' mixture, I don't know how such few extra Btus could make a 'showing' at the crankshaft and flywheel.
12) I had auto shop all the way through high school, and a junior-college engine-building course while in the military, and instructors insisted that one should NEVER use additives of any type in an automobile.
Caveat Emptor.

Perhaps I should have pointed out the link was into Unicorn Corral?

My feelings about ethanol.

ethanol
 

Whoever sponsored the legislation for this variety of mandated oxygenate probably received attractive campaign financing from the corn lobby in subsequent elections.
I was pleased to see the Methyl Tertiary Butyl Ether ( MTBE ) banned, although we'll pay for it until time ends because of Clinton's Mutual Agreement on Investments.