Fuel octane how to calculate test?

Answer 1

US octane rating is the average of RON rating and MON rating. Research Octane Number (RON). RON is determined by running the fuel in a test engine with a variable compression ratio under controlled conditions. Motor Octane Number(MON), which is a better measure of how the fuel behaves when under load, as it is determined at 900 rpm engine speed, instead of the 600 rpm for RON.[1] MON testing uses a similar test engine to that used in RON testing, but with a preheated fuel mixture, higher engine speed, and variable ignition timing to further stress the fuel's knock resistance. Depending on the composition of the fuel, the MON of a modern gasoline will be about 8 to 10 points lower than the RON. When you go to the pump, you will see a yellow sticker showing that the rating is the average of the two.(in us) I think Europe is different.