I've wondered that too, for my 48 international....dont know what the compression ratio is, but I know it meant to run on no-lead 86 octane!
The people that make Sta-Bil now market an additive they claim counteracts the effects of Ethanol in gas. Haven't tried it. Also, there's stations here and there that sell pure gasoline, but at a premium price. Dave
Model As and Ts and other cars of their era don't care what gas you use today. Any of it is better than the gas that was available back when they were new and Ts would run on kerosene.
Pure gas no Ethanol would be my choice, also a half gallon of 112 Leaded Sunoco per tank to help with valve seat cushioning!
There was no lead in gasoline when a Model A was new so I find it kind of comical that people think they need a lead additive.
Check out an additive called startron, alot of the vintage tractor guys use it. I read about it and sounds like good stuff. My neighbor just picked some up at wal-mart in the marine section.
Who told you that? Tetraethyllead (common name tetraethyl lead), (CH<sub>3</sub>CH<sub>2</sub>)<sub>4</sub>Pb has been added to gasoline since the 1920's. Lead works as a buffer against microwelds forming between the hot exhaust valves and their seats. Lead usage for performance usage wasn't prominent until after WWII.
Great info guys, thanks. I totally LOVE the sound of a 4-banger, and plan to run it. Would like to add a dual intake and alum exhaust manifold, then drive the hell out of her.
Lead may have been added to gasoline starting in the 20's, but in very limited amounts and in the Model A era was in no way a requirement to operate the engine successfully. Engines didnt start really needing the lead until after WWII with the advent of high compression, which was introduced by the automakers working with the oil companies to introduce high octane leaded fuel at the same time. By the 20's, cars had already been built for over 20 years including 15 million model T's and countless tractors, etc., none of which required lead to run many thousands of miles successfully. Most antique cars with low compression engines don't require any type of additive to the gas.
The model A, with the iron zenith carb, will run on almost anything you put through it....including ethanol. The Model T was actually designed to run on alcohol as "the fuel of the future".....little bit of usless knowlage there. I personally run whatever comes out of the pump, with an occasional bottle of "seafoam" ever 500-600 miles. I haven't had any issues yet.