Fast forward to 1950 and the race rules were changed to allow for 6.6-liter diesel engines, prompting the birth of the Cummins Green Hornet. It sported a streamlined body made by chassis designer Kurtis-Kraft. It was powered by a turbocharged 6.6-liter oil burner capable of making up to 340 horsepower.
But the Green Hornet barely qualified for the 1950 race. As such, Cummins skipped the 1951 season and focused on improving its race weapon with a new suspension system, lighter magnesium and aluminum engine components, and a turbocharger. Its engine was likewise tilted to lower its center of balance, and its output was bumped up to 380 hp.
On that note, the subsequent Cummins Indy 500 racer project was the first car to have ever used a turbocharger in the history of the motorsport event, and the only turbodiesel Indycar ever made. It was also the first aerodynamically viable car that raced in the famous race event.
