<P> The event is steeped in tradition, in pre-race ceremonies, post-race celebrations, and race procedure . The most noteworthy and most popular traditions are the 33 - car field, the annual singing of "Back Home Again in Indiana," and the victory lane bottle of milk . </P> <P> The Indianapolis 500 is held annually at the Indianapolis Motor Speedway, a 2.5 - mile (4.0 km) oval circuit . Technically, IMS is a rounded - rectangle, with four distinct corners of identical dimensions referred to as "turns", and four straightaways (2 long and 2 short). Drivers race 200 laps, counter-clockwise around the circuit, for a distance of 500 miles (800 km). Since its inception in 1911, the race has always been scheduled on or around Memorial Day . Since 1974, the race has been specifically scheduled for the Sunday of Memorial Day weekend . Practice and time trials are held in the two weeks leading up to the race . The Sunday of Memorial Day weekend is widely considered one of the most important days on the motorsports calendar, as it is the day of the Indianapolis 500, Coca - Cola 600, and (currently) the Monaco Grand Prix . </P> <P> Traditionally, the field consists of 33 starters, aligned in a starting grid of eleven rows of three cars apiece . The event is contested by "Indy cars", a formula of professional - level, single - seat, open cockpit, open - wheel, purpose - built race cars . As of 2018, all entrants utilize 2.2 L V6, twin - turbocharged engines, tuned to produce a range of 550--700 horsepower (410--520 kW). Chevrolet and Honda are the current engine manufacturers involved in the sport . Dallara is at present the sole chassis supplier to the series . Firestone, which has a deep history in the sport, dating back to the first 500, is currently the exclusive tire provider . </P> <P> The race is the most prestigious event of the IndyCar calendar, and one of the oldest and most important automobile races . It has been avouched to be the largest single - day sporting event in the entire world . Likewise, the Indianapolis Motor Speedway itself is regarded as the world's largest sporting facility in terms of capacity . The total purse exceeded $13 million in 2011, with over $2.5 million awarded to the winner, making it one of the richest cash prize funds in sports . </P>

What kind of car races in the indy 500
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