Thompson brought three modified 12-inch-tired cars to the 1964 Indianapolis 500, but new rules required him to use 15-in tires. The Allstate sponsored team used Allstate tires and Ford engines. The chassis had to be altered to accommodate the larger Ford engines. Two of them qualified for the race. The car No. 84 began the month with Masten Gregory as the driver, but Eddie Johnson in car No. 84 qualified 24th and finished 26th. Dave MacDonald in car No. 83 qualified 14th and died in a fiery crash on the second lap.