Briggs Cunningham prepared his stable of entries. Luigi Chinetti and Alfredo Momo looked over the Ferrari they would drive. John Fitch, Jim Kimberly, Fred Wacker, Phil Walters, and Bill Spear, they all circulated through the pits as exhaust notes from Jaguars, Astons, and MGs rapped, roared, and rumbled. The former Hendricks Army Airfield buzzed with activity as American sports car racing’s most well-known names of the time gathered for the first race of what was billed as America’s counterpart to the 24 Hours of Le Mans, each driver and car owner as confident as the rest of their abilities to win the race.

Even the trio gathered around a 1949 Crosley Hotshot way down at the back of the 28-car field, a car that had only been entered in the race a day before and that had an advantage the far more powerful cars ahead of it didn’t: math.

Alec Ulmann had taken part in the 24 Hours of Le Mans many times before World War II and after immigrating to the United States looked for a place to replicate the famed race. Though its surface was bumpy and better suited to the B-17 bombers that flew out of the base during the war, Ulmann decided to focus his efforts on the runways and access roads of what had become Sebring’s municipal airport. His initial effort, slated for December 31, 1950, didn’t have the length of Circuit de la Sarthe (3.5 miles versus 8.4) or the duration (six hours versus 24) but it would have a Le Mans-style running start, the blessing of the SCCA, the aforementioned drivers and owners, and an index of performance.

At many other endurance races before and since, overall winners completed the most laps in the given amount of time. Different classes of cars might take to the track at the same time and have their own separate class winners, but the method of winning still boiled down to the same criteria of distance covered. With the index of performance, which set a target distance to cover based on the vehicle’s engine displacement and which would be the sole deciding factor for the overall winner of the race, Ulmann intended to level the playing field and ensure that smaller cars could compete against larger cars. As Sports Illustrated explained the index a few years later, the index actually favors small cars.

The small cars … can generally exceed their set minimum average by a wider margin than the big ones. Thus, if you are driving a 66 cu. in. machine and have to average 58 mph, it is easier to up this average by 10 mph than with a 330 cu. in. car which must average 70 mph, all pit stops included.

Nobody at the race seemed to realize the full implications of Ulmann’s decision to declare the overall winner based on the index of performance until Tommy Cole laid eyes on a most unusual car. Cole, who had entered a Cadillac-powered Allard J2 in that inaugural Sebring race and who had raced at Le Mans earlier that year, needed tires and called around Florida Cadillac dealerships until somebody at Vic Sharpe’s Cadillac dealership in Tampa answered the phone. Sharpe also held the local Crosley franchise, and his son, Vic Sharpe Jr., volunteered to drive the tires down to Sebring in a Crosley Hotshot on the dealership lot. Almost as soon as Sharpe arrived, according to Ken Breslauer’s account of that first Sebring race, Cole looked over the Hotshot, questioned Sharpe about its cast-iron overhead-camshaft 724-cubic-centimeter four-cylinder, and asked to take it around the track that Ulmann had laid out.

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