Red Line SL-1 use to have directions on the bottle to use 4.55 mL per U.S. gallon of gasoline for maintenance. That is the dose I still use. You can buy graduated cylinders of different sizes at McMaster-Carr. I carry the 100 mL graduated cylinder in my vehicle along with a bottle of Red Line SL-1 and put what I calculate to be 4.55 mL of Red Line SL-1 in the gas-tank before each fill up to keep the fuel metering parts of the engine clean.
Red Line SL-1 is a very slippery oil, along with being a cleaner, it is also an upper cylinder lube. Also it is very easy to get on your hands, so I usually either wear gloves or wash my hands after using it, or both. Also, it is hydroscopic, meaning that it attracts water. If you store the graduated cylinder upright after using it, the little bit left on the surface of the graduated cylinder will actually cause water to condense out of the air and there will be about a mL or more water in the cylinder the next time you go to use it.
I store the cylinder upside down in several plastic bags and the water accumulates in the bottom of the bag.
There was some post that suggest that the lucubrating ability of the SL-1 is so that it reduces the piston friction enough to improve the MPG enough to pay for the cost of using it. I do not know it that is true or not, but it might be.
