It was a paved1/3 of a mile banked track. Most of the tracks back then were 1/4 paved flat tracks or 1/2 mile dirt tracks. Sportsman cars were not allowed quick changed rear ends, so to find a correct gear with a stock rear end proved difficult.
Standard rear ends were 378, V 6s were 411, 1940 Sedan Deliverys were 444 and some 3/4 Ton Pick ups were 667.
Diameter of rear tires helped a little.
Problems,Problems Problems!
Of course you could always run Lincoln gears in the transmission with a Mercury rear end 327.
updated by @jim-streeter: 12/05/16 04:00:58PM