On Feb. 2, 1923, the first Ethyl gasoline went on sale at a roadside station in Dayton.
In those days, gasoline caused car engines to knock or ping. It was not only annoying, but potentially harmful to the engine.
Thomas Midgely and Charles Kettering, researchers for General Motors in Dayton, discovered that adding tetraethyl lead to the gas eliminated the problem. Kettering coined the resulting mixture "ethyl gasoline," which was dyed red to distinguish it from regular gas.
It was first made available to motorists at a Dayton gas station owned by Willard Talbott, a friend of Kettering. Of course, leaded gasoline was toxic to the environment and to people.
By the mid-1930s a collaboration among General Motors, DuPont and Standard Oil produced Ethyl gas. They managed to suppress government reports about the danger of the product and tetraethyl lead was added to 90 percent of the gasoline used in the United States. Leaded gas was phased out in the 1970s.
Compression ratio of the engine has a lot to do with it, also. As the compression ratio of performance engines increased, the increased octane and tetraethyl lead was necessary to keep the old hotrod going strong without burning valves and other parts. Not all early engines had hardened valve seats, so when the government made us go to lead free gas, a lot of older engines suffered mechanically and of course performance wise also. I miss the days of pulling up to the pump with the 427 and filling it with 106 or 108 octane (old rating) premium (.36 a gal.)and heading out to dust off some Fords and Mopars. A couple quick street races usually paid for weekend activities and refreshments. Now I have this weiner, but cool looking, flathead with 100HP--about 1/4 the HP of the 427.