Robroy. I have an interest in octane ratings and fuel combustibility due to a hobby of restoring antique farm equipment. My current project, almost complete, is the total restoration of my 1953 Ferguson TEA20 tractor.
High octane fuel has high aromatics content, and very low olefins (alkenes). Conversely, low octane has low aromatics and higher combustibility. Parafin (kerosene, heating oil) has an octane rating of zero.
During the war gasoline was rationed and restricted but governments had lashings of zero octane kerosene and, seeing as Mr Whittle's invention was yet to be built in large numbers to consume the kerosene, old tractors often use Tractor Vaporising Oil (TVO) or power kerosene, with far lower octane rating. As a result, old engines had far lower compression ratios to avoid pre ignition as the low octane fuel was far more combustible.)
Power kerosene or TVO is approximately three parts lighting kerosene, one part standard gasoline and reduces the octane rating to 55 to 70.
Here ends the science lesson!!
Des, someone in here had Mike Thomas's record and I think transferred it to tape or disk.
I'm sure if you offer free beer, all the geriatrics will be here!