It’s Indy 500 time, and to celebrate, the diesel gurus at Cummins have posted up a reflection of the engine builder’s history in the iconic race.
According to the blog post at Cummins’ website, company namesake Clessie Cummins was a mechanic on the winning Marmon Wasp in the first Indianapolis 500 way back in 1911. From there, it was only a hop and a skip– and a handful of years– before Cummins was trying on a more radical hat as a full-fledged engine builder at the Brickyard:
1931…The Great Depression was hitting hard during the race’s 20th year. Indianapolis Motor Speedway owner Eddie Rickenbacker was having a tough time finding cars to fill out the field, but letting a diesel-powered car into the race was unheard of. There were not any rules governing diesels, and the AAA’s contest board had to allow the diesel car to race as a special engineering entry because the car was too heavy and the engine displacement too large to qualify under existing rules.
Cummins didn’t expect to win, but he and his crew had a different achievement in mind – he just wanted a chance to show the world the fuel efficiency and durability of the diesel engine. The #8 Cummins Special qualified with an average speed of 97 mph. Two days later, with Dave Evans behind the wheel, it became the first entry ever to run the entire race nonstop, finishing 13th on just $1.40 worth of “furnace oil.”
After that landmark performance, Cummins would become even more involved in racing at the legendary track all the way up to the late ’80s. Per the website:
1934 – The race track becomes a test track. Three years after running the Cummins Special at the track, Cummins returned with not just one, but two competing engines. Cummins was interested in testing the effectiveness of 2-cycle versus 4-cycle designs for durability and efficiency. During the race, the 2-cycle engine had numerous issues while the 4-stroke ran smoothly — until the 270-mile mark, when the driver stripped the gears pulling out of his very first pit stop. The test may have sealed the fate of the 2-cycle engine –Cummins diesels have been 4-cycle ever since.
1950 – Speed records fall to “The Green Hornet.” Sixteen years passed before a Cummins diesel appeared again at the Indianapolis Speedway. By then, Cummins engines were a staple of the commercial trucking industry, and Cummins engineers wanted to demonstrate that these workhorses could also run like thoroughbreds. They crafted a 4-cycle Cummins Model JS-600 engine in lightweight aluminum, and added a supercharger. The engine used for qualifying produced 345 brake horsepower (bhp) at 4,000 rpm.
Dubbed “The Green Hornet,” the car qualified at 129 mph and started in 33rd position. On race day, it steadily picked off half the field, and was in 16th position when a mechanical failure forced it out of the race. Later that year, the same Cummins race car would set six U.S. and international land speed records at the Bonneville Salt Flats.
1952 – The only diesel ever to capture the pole. In 1952, Cummins returned to the Indy 500 with another innovation new to the speedway: turbocharging. The car had a unique side-lying engine design, which enabled an offset drivetrain and lower center of gravity for better handling on the banked turns. The #28 Cummins Diesel Special was also the first Indy car ever tested in a wind tunnel for aerodynamics.
The results were amazing. Freddie Agabashian took #28 out on the brickyard and tore the tread off of his front right tire while capturing the pole with the fastest one-lap time (139.104 mph) and four-lap time (138.010 mph) in Indianapolis Motor Speedway history. The Cummins Diesel Special was retired midway through the race as the turbocharger inlet became clogged with rubber debris from the track – but it had established turbocharging as a viable technology on the track, as well as helped engineers refine improvements to the breakthrough Cummins PT fuel system.
1987 – A last-minute entry races into the history books. The 1987 Cummins car’s sponsorship was a result of several last-minute decisions. The car itself had actually been previously retired from racing and was on display in a hotel lobby. Two weeks before the race, Cummins and Penske Racing teamed up to sponsor the car and enter the race, and at the last minute the #25 Cummins Holset car found a driver who knew a thing or two about racing – three-time Indy 500 winner Al Unser Sr. Unser employed some outstanding pit strategy throughout the race, finally moving into first position on the white-flag lap for the win.
While this year’s field will feature only Honda and Chevrolet gassers, we’d certainly like to see what could be done with a modern diesel powerplant in a new-age Indycar chassis. After all, diesel works wonders for Audi in the American Le Mans Series.