Indianapolis 500

The Indianapolis 500-Mile Race is the world's oldest currently operational automobile race. Better known as the Indy 500 or the Indianapolis 500, it is held annually at the Indianapolis Motor Speedway (IMS) in Speedway, Indiana, United States, an enclave suburb of Indianapolis, Indiana. The event is traditionally held over Memorial Day weekend in late May. It is contested as part of the IndyCar Series, the top level of American Championship Car racing, an open-wheel open-cockpit formula colloquially known as "Indy Car Racing". The name of the race is often shortened to Indy 500, and the track itself is nicknamed the "Brickyard", as the racing surface was paved in brick in the fall of 1909, with a yard of brick remaining exposed at the start/finish line.

The event billed as The Greatest Spectacle in Racing is considered part of the Triple Crown of Motorsport, which comprises three of the most prestigious motorsports events in the world, also including the Monaco Grand Prix (which traditionally falls on the same day as the Indianapolis 500) and the 24 Hours of Le Mans. In two different periods the race was part of FIA World Championships; between 1925-1928 the World Manufacturers' Championship and between 1950-1960 the Formula One World Championship. The official attendance is not disclosed by Speedway management, but the permanent seating capacity is upwards of 250,000, and infield patrons raise the race-day attendance to approximately 300,000. It shares its date with NASCAR's 600-mile event at Charlotte, with drivers having completed both events in one day before in a so-called Double Duty.

The inaugural race was held in 1911 and was won by Ray Harroun. The event celebrated its 100th anniversary in 2011, and the 100th running was held in 2016. The event was put on hiatus twice, from 1917 to 1918 due to World War I and from 1942 to 1945 due to World War II. Simon Pagenaud is the current champion. The most successful drivers are A. J. Foyt, Al Unser Sr., and Rick Mears, each of whom have won the race four times. The active driver with the most victories is Hélio Castroneves, with three. Rick Mears holds the record for most career pole positions with six. The most successful car owner is Roger Penske, owner of Team Penske, which has 18 total wins and 18 poles. Penske also has five wins at the IndyCar Grand Prix, held on the combined road course.

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 lining up three-wide for the start, the annual singing of "Back Home Again in Indiana," and the victory lane bottle of milk. Also unique is that qualifying requires the driver to complete four, rather than one, timed laps and qualifying itself has a separate weekend.

Race specifics
The Indianapolis 500 is held annually at the Indianapolis Motor Speedway, a 2.5 mi oval circuit. The track is a rounded-rectangle, with four distinct turns of identical dimensions, connected by four straightaways (two long straightaways and two "short chutes"). Drivers race 200 laps, counter-clockwise around the circuit, for a distance of 500 mi. 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. 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. Practice and time trials are held in the two weeks leading up to the race, while miscellaneous preliminary testing is held as early as April.

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 2020, all entrants utilize 2.2 L V6, twin-turbocharged engines, tuned to produce a range of 550 - 700 hp. 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.

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.

Similar to NASCAR's Daytona 500, the Indianapolis 500 is typically held early in the IndyCar Series season. That is unique to most sports where major events are usually at the end of the respective season. Currently, the Indy 500 is the sixth event of the 17-race IndyCar schedule. From the 1970s to the 1990s, Indianapolis was often the second or third race of the season, and as late as the 1950s, it was sometimes the first championship event of the year. Due to the high prestige of the Indianapolis 500—rivaling or even surpassing the season championship—it is not uncommon for some teams and drivers to focus heavily on preparing for that race during the early part of the season, and not focus fully on the championship battle until after Indy.

Due to safety issues such as aquaplaning, the race is not held in wet conditions. In the event of a rain delay, the race will be postponed until rain showers cease, and the track is sufficiently dried. If rain falls during the race, officials can end the race and declare the results official if more than half of the scheduled distance (i.e., 101 laps) has been completed. The Indianapolis 500, as well as other IndyCar Series races, does not utilize the green–white–checker finish in case of a late-race yellow. The race can be (and in the past has been) finished under caution. However, officials may call for a late-race red flag to ensure a green-flag finish, an option that was used in 2014 and 2019. The circuit lacks lights, therefore lateness can become a factor in the cases of lengthy delays.

Field
The traditional 33-car starting field at Indianapolis is larger than the fields at the other IndyCar races. The field at Indy typically consists of all of the full-time IndyCar Series entries (roughly 20–22 cars), along with 10–15 part-time or "Indy-only" entries. The "Indy-only" entries, also known as "One-Offs", may be an extra car added to an existing full-time team, or a part-time team altogether that does not enter any of the other races, or enters only a few selected races. The "Indy-only" drivers may come from a wide range of pedigrees but are usually experienced Indy car competitors that either lack a full-time ride, are former full-time drivers that have elected to drop down to part-time status, or occasional one-off drivers from other racing disciplines. It is not uncommon for some drivers (particularly former Indy 500 winners) to quit full-time driving during the season, but race at Indy singly for numerous years afterward before entering full retirement.

The early years


The Indianapolis Motor Speedway complex was built in 1909 as a gravel-and-tar track and hosted a smattering of small events, including ones for motorcycles. The first long-distance event, in "fearful conditions," was the 100-lap Prest-O-Lite Trophy in 1909, won by Bob Burman in a Buick. The breakup of the track surface led to two fatal accidents in the first two long-distance events (a 250 mi and 300 mi, which was shortened to 235 mi after two severe wrecks).

That these spectacles had attracted 15,000 paying customers (and crowds of up to 40,000) persuaded principal owner Carl G. Fisher to spend $155,000 on repaving the track with 3.2 million bricks; he also added a 33 in concrete wall around the track's circumference. During the 1910 Decoration Day weekend, the first events on the newly paved circuit drew 60,000 spectators; Ray Harroun won the 200 mi Wheeler-Schebler Trophy in a Marmon.

The crowds grew progressively smaller for the rest of the season, however, so the track owners chose to focus on a single race, and considered a 24-hour contest, in the fashion of Le Mans, or a 1000 mi event. They decided on 500 mi, the estimated distance a race car could run before dark descended on the track, and a spectacular purse of $25,000, equivalent to 82.93 lb of pure gold. The combination allowed the track to rapidly acquire a privileged status for automobile races.

The first "500" was held at the Speedway in 1911 on Decoration Day, May 30, (as it was known from its inception in 1868 to 1967, when federal law made "Memorial Day" the official name), run to a 600 cid maximum engine size formula. It saw a field of 40 starters, with Harroun piloting a Marmon Model 32-based Wasp racer—outfitted with his invention, the rear-view mirror. Harroun (with relief from Cyrus Patschke) was declared the winner, although Ralph Mulford protested the official result. Eighty thousand spectators were in attendance, and an annual tradition had been established. Many considered Harroun to be a hazard during the race, as he was the only driver in the race driving without a riding mechanic, who checked the oil pressure and let the driver know when traffic was coming.

In 1912, the purse was raised to $50,000, the field was limited to 33 (where it remains), and a riding mechanic was made mandatory. This second event was won by Joe Dawson in a National, after Ralph de Palma's Mercedes broke. Although the first race was won by an American driver at the wheel of an American car, European makers such as the Italian Fiat or French Peugeot companies soon developed their vehicles to try to win the event, which they did from 1912 to 1919. The 1913 event saw a change to a 450 cid maximum engine size.

After World War I, the native drivers and manufacturers regained their dominance of the race, and engineer Harry Miller set himself up as the most competitive of the post-war builders. His technical developments allowed him to be indirectly connected to a history of success that would last into the mid-1970s.

For musical entertainment before the start of the race, the Purdue All-American Marching Band has been the host band of the race since 1919. In 1946, American operatic tenor and car enthusiast James Melton started the tradition of singing "Back Home Again in Indiana" with the Purdue Band before the race when asked to do so on the spur of the moment by Speedway president Tony Hulman. This tradition has continued through the years, notably by actor and singer Jim Nabors from 1972 until 2014. Nabors announced in 2014, citing health-related reasons, that the 2014 Indy 500 would be the last at which he would sing the song. In 2015, the a cappella group Straight No Chaser sang the song before the race, and in the two races held after Nabors' retirement (and before he became the regular singer), the singing of the song was done on a rotating basis, with the Spring 2014 winner of The Voice Josh Kaufman performing in 2016. However, the Speedway has returned to a standard singer starting in 2017, with Jim Cornelison doing it for three races as of the 2019 race.

Miller and Offenhauser


Following the European trends, engine sizes were limited to 183 cid during 1920–1922, 122 cid for 1923–1925, and 91 cid in 1926–1929. The 1920 race was won by Gaston Chevrolet in a Frontenac, prepared by his brothers, powered by the first eight-cylinder engine to win the 500. For 1923, riding mechanics were no longer required. A supercharged car, ID, first won the race in 1924. In 1925, Pete DePaolo was the first to win at an average over 100 mph, with a speed of 101.13 mph.

In the early 1920s, Miller built his 3.0-liter (183 in3) engine, inspired by the Peugeot Grand Prix engine which had been serviced in his shop by Fred Offenhauser in 1914, installing it in Jimmy Murphy's Duesenberg and allowing him to win the 1922 edition of the race. Miller then created his own automobiles, which shared the 'Miller' designation, which, in turn, were powered by supercharged versions of his 2.0- and 1.5-liter (122 and 91 in3) engine single-seaters, winning four more races for the engine up to 1929 (two of them, 1926 and 1928, in Miller chassis). The engines powered another seven winners until 1938 (two of them, 1930 and 1932, in Miller chassis), then ran at first with stock-type motors before later being adjusted to the international 3.0-liter formula.

After purchasing the Speedway in 1927, Eddie Rickenbacker prohibited supercharging and increased the displacement limit to 366 cid, while also re-introducing the riding mechanic.

In 1935, Miller's former employees, Fred Offenhauser, and Leo Goosen, had already achieved their first win with the soon-to-become famous 4-cylinder Offenhauser or "Offy" engine. This motor was forever connected with the Brickyard's history with a to-date record total of 27 wins, in both naturally aspirated and supercharged form, and winning a likewise record-holding 18 consecutive years between 1947 and 1964.

European incursions and links to Formula One
Meanwhile, European manufacturers, gone from the Indianapolis 500 for nearly two decades, made a brief return just before World War II, with the competitive Maserati 8CTF allowing Wilbur Shaw to become the first driver to win consecutively at Indianapolis, in 1939 and 1940. With the 500 having been a part of the World Drivers' Championship between 1950 and 1960, Ferrari made a discreet appearance at the 1952 event with Alberto Ascari, but European entries were few and far between during those days. Among the Formula One drivers who did drive at the speedway was five-time world champion, Argentinian Juan Manuel Fangio, though he failed to qualify for the 1958 race.

It was not until the Indianapolis 500 was removed from the World Championship calendar that European entries made their return. In 1963, technical innovator Colin Chapman brought his Team Lotus to Indianapolis for the first time, attracted by the large monetary prizes, far bigger than the usual at a European event. Racing a mid-engined car, Scotsman Jim Clark was second in his first attempt in 1963, dominating in 1964 until suffering suspension failure on lap 47, and completely dominating the race in 1965, a victory which also interrupted the success of the Offy, and giving the 4.2-liter Ford V8 its first success at the race. The following year, 1966, saw another British win, this time Graham Hill in a Lola-Ford.

The Offenhauser engine was also paired with a European maker, McLaren, obtaining three wins for the chassis, one with the Penske team in 1972 with driver Mark Donohue, and two for the McLaren works team in 1974 and 1976 with Johnny Rutherford. This was also the last time the Offy would win a race, its competitiveness steadily decreasing until its final appearance in 1983. American drivers continued to fill the majority of entries at the Brickyard in the following years, but European technology had taken over. Starting in 1978, most chassis and engines were European, with the only American-based chassis to win during the CART era being the Wildcat and Galmer (which was technically built in Bicester, England) in 1982 and 1992, respectively. Ford and Chevrolet engines were built in the UK by Cosworth and Ilmor, respectively.

Fernando Alonso was the most recent active Formula One driver to race at the Indy 500-mile race, in 2017. Before that, no active F1 driver had competed in the Indy 500 since 1984.

World Series


After foreign cars became the norm, foreign drivers began competing in the Indianapolis 500 regularly, choosing the United States as their primary base for their motor racing activities. Brazilian Emerson Fittipaldi, Italian Teo Fabi, and Colombian Roberto Guerrero were able to obtain good outings in the 1980s, as was Dutchman Arie Luyendyk. However, it was not until 1993 that reigning Formula One World Champion Nigel Mansell shocked the racing world by moving to the United States, winning the CART PPG IndyCar World Series Championship and only losing the 500 in his rookie year because of inexperience with green-flag restarts. Foreign-born drivers became a regular fixture of Indianapolis in the years to follow. Despite the increase in foreign drivers commonly being associated with the CART era, four of the first six Indianapolis 500 winners were non-American drivers.

Race name
The race was originally advertised as the "International 500-Mile Sweepstakes Race" from 1911 to 1916. However, from its inception, the race has been widely known as the Indianapolis 500 or, more simply as "the 500". In 1919, the race was referred to as the "Liberty Sweepstakes" following WWI. From 1920 to 1980, the race officially reverted to the "International Sweepstakes" moniker, as printed on the tickets and other paraphernalia, with slight variations over the years.

Following WWII, the race was commonly recognized as "The 500", "The 500-Mile Race", "Indianapolis 500-Mile Race", "Indianapolis 500", or the simple form "Indy 500". Usually the ordinal (e.g. "50th") preceded it. Often the race was also advertised on the radio as the "Annual Memorial Day race," or similar variations.

For the 1981 race, the name "65th Indianapolis 500-Mile Race" was officially adopted, with all references as the "International Sweepstakes" dropped. Since 1981, the race has been formally advertised in this fashion, complete with a unique annual logo with the ordinal almost always included. Around that same time, in the wake of the 1979 entry controversy, and the formation of CART, the race changed to an invitational event, rather than an Open, rendering the "sweepstakes" description inappropriate.

For nearly a century, the race eschewed any sort of naming rights or title sponsor, a move, though uncommon in the modern sports world, that was well-received by fans. This tradition finally ended in 2016 when a presenting sponsor, PennGrade, was added for the first time. In the 21st century, the facility has also slowly added sponsorship ads on the retaining walls and infield grass. The ESPN-produced ABC telecast of the event did not recognize this sponsorship and instead had Firestone Tires as its presenting sponsorship.

The Borg-Warner Trophy, introduced in 1936, proclaims the event as the "Indianapolis 500-Mile Race", with no reference at all to the name "International Sweepstakes".

Centennial Era
In 2009, the Indianapolis Motor Speedway began a three-year-long "Centennial Era" to celebrate the 100th anniversary of the opening of the track (1909), and the 100th anniversary of the first Indy 500 (1911). As a gesture to the nostalgic Centennial Era celebration (2009–2011), tickets for the 2009 race donned the moniker "93rd 500 Mile International Sweepstakes". It is the first time since 1980 that the "Sweepstakes" title has been used. During the month of May 2009, the ordinal (93rd) was used very sparingly, and for the first time since 1981, was not identified on the annual logo. Instead, in most instances in print, television, and radio, the race was referred to as the "2009 Indianapolis 500". Since the race was not held during the United States' participation in the two World Wars (1917–1918, 1942–1945), the advertised Centennial Era occurred during the 93rd to 95th runnings. To avoid confusion between the 100th anniversary, and the actual number of times the race has been run, references to the ordinal during the Centennial Era were curtailed.

Six years later, in 2016, the race celebrated its 100th running with about 350,000 in attendance.

Female drivers


Female participation of any sort at Indianapolis was discouraged and essentially banned throughout the first several decades of competition. As such, female reporters were not even allowed in the pit area until 1971. There have been nine female drivers to qualify, starting with Janet Guthrie in 1977.

Sarah Fisher has competed nine times, the most of any woman. Danica Patrick led 19 laps in the 2005 race and ten laps in the 2011 race, the only times a woman has led laps during the race. Pippa Mann has raced in Indy five consecutive times between 2013 and 2017.

AAA and USAC


From 1911 to 1955, the race was organized under the auspices of the AAA Contest Board. Following the 1955 Le Mans disaster, AAA dissolved the Contest Board to concentrate on its membership program aimed at the general motoring public. Speedway owner Tony Hulman founded USAC in 1956, which took over sanctioning of the race and the sport of Championship racing.

From 1950 to 1960, the Indianapolis 500 also counted toward the FIA's World Championship of Drivers (now synonymous with Formula One), although few drivers participated in the other races of that series. Italian driver Alberto Ascari was the only European-based driver to race in the 500 during its World Championship years. His appearance in 1952 in a Ferrari was also the only time a Ferrari has ever appeared in the race. Juan Manuel Fangio practiced at the track in 1958 but declined an offer to race.

Control issues of monetary prizes and squabbles over technical regulations caused conflict in the 1970s. Soon after the death of Tony Hulman in 1977, and the loss of several key USAC officials in a 1978 plane crash, several key team owners banded together and formed CART in late 1978 to sanction the sport of Indy car racing.

The Indianapolis 500 itself, however, remained under the sanctioning control of USAC. It became the lone top-level race the body still sanctioned, as it ultimately dropped all other Indy car races (as well as their stock car division) to concentrate on sprints and midgets. For the next three years, the race was not officially recognized on the CART calendar, but the CART teams and drivers comprised the field. By 1983, an agreement was made for the USAC-sanctioned Indy 500 to be recognized on the CART calendar, and the race awarded points towards the CART championship.

Despite the CART/USAC divide, from 1983 to 1995 the race was run in relative harmony. CART and USAC occasionally quarreled over relatively minor technical regulations but utilized the same machines and the CART-based teams and driver comprised the bulk of the Indy 500 entries each year.

IndyCar Series


In 1994, Speedway owner Tony George announced plans for a new series, to be called the Indy Racing League, with Indy 500 as its centerpiece. George announced that he intended to reverse the tide of dramatic cost increases, the decreasing number of ovals in the CART series, and to allow for more opportunity for drivers from USAC sprint-car ranks. Detractors accused George of using the 500 as leverage to allow the Speedway to gain complete control of the sport of open-wheel racing in the United States.

In response to CART's 1996 schedule that put several races in direct conflict with the first Indy Racing League events, George announced that 25 of the 33 starting positions at the 1996 Indy 500 would be reserved for the top 25 cars in IRL points standings. This effectively left eight starting positions open to the CART-regulars that chose not to participate in the IRL races and would be the first time that not all 33 spots were open for qualification in the history of the race. CART refused to compromise on the schedule conflicts, skip the IRL races required to accumulate the qualifying points, boycott the race, and stage a competing event, the U.S. 500, on the same day at Michigan. Veteran Buddy Lazier won a competitive but crash-filled 1996 Indy 500. Two CART teams, Walker Racing and Galles Racing, competed in the Indianapolis 500 to fulfill sponsor obligations and were welcomed without incident. The U.S. 500, meanwhile was marred by a crash on the pace laps that forced ten teams to use backup cars.



For 1997, new rules for less expensive cars and "production-based" engines were put into place. The move made it such that the IRL utilized different and incompatible equipment from CART; no CART-based teams would enter the Indy 500 for the next three years. CART would run a 300-mile race Gateway International Raceway on the Saturday of Memorial Day weekend from 1997–1999 to avoid a conflict.

In 2000, Target Chip Ganassi Racing, still a CART-mainstay, decided to compete at Indianapolis with drivers Jimmy Vasser and Juan Pablo Montoya. On race day, Montoya dominated the event, leading 167 of the 200 laps to victory. In 2001, Penske Racing returned and won the race with driver Hélio Castroneves. Penske and Castroneves repeated with a win in 2002.

By 2003, Ganassi, Penske and Andretti Green defected to the IRL permanently. CART went bankrupt later in the year, and its rights and infrastructure were purchased by remaining car owners, and it became the Champ Car World Series. The two series continued to operate separately through 2007. In early 2008, the two series were unified to create a single open-wheel championship after a 12-year split being run under Indy Racing League/IMS control—known as the IndyCar Series.

The 2012 race was the return of Turbocharged engines for the first time since 1996 with the use of the Dallara DW12 chassis and 2.2 L V-6 single-turbo and twin-turbocharged engines.

NASCAR and the 500
In the 1960s and early 1970s, the Indy 500 and the World 600 (now known as the Coca-Cola 600) at Charlotte Motor Speedway were held on different days of the week. A handful of NASCAR regulars participated in both events in the same year, including Bobby Allison, Donnie Allison, Cale Yarborough, and Lee Roy Yarbrough. From 1974 to 1992, the two events were scheduled for the same day and same starting time, making participation in both impossible. A few stock car drivers during that time, namely Neil Bonnett in 1979, nevertheless still attempted to qualify at Indy, even if that meant skipping Charlotte altogether.

"Double Duty"
From 1994 to 2014, several NASCAR drivers were able to compete in both the Indy 500 and the Coca-Cola 600 at Charlotte on the same day. Since 1993, the Coca-Cola 600 has been scheduled in the evening the same day as the Indy 500. The effort has been known as "Double Duty". After the Indy 500, drivers would catch a helicopter directly from the Speedway to the Indianapolis International Airport. From there they would fly to Concord Regional Airport, and ride a helicopter to the NASCAR race. John Andretti, Tony Stewart, and Robby Gordon attempted the feat, with Kurt Busch being the latest in 2014. In 2001, Tony Stewart became the first driver to complete the full race distance (1,100 miles) in both races on the same day.

For 2005, the start of Indianapolis was pushed back to 1 p.m. EDT to improve television ratings. This significantly closed the window for a driver to be able to race both events on the same day. (The race's original starting time had been set at 11 a.m. EST to 12 noon EDT—because in 1911, race promoters estimated it would take six hours to complete the event, and they did not want the race to finish too close to dinnertime. Nowadays, the race is routinely completed in under three-and-a-half hours.)

Two drivers, Mario Andretti and A. J. Foyt, have won the Indianapolis 500 and the Daytona 500. Foyt also won the 24 Hours of Daytona and 12 Hours of Sebring, America's premier endurance races, as well as the 24 Hours of Le Mans. Foyt won Le Mans in 1967, about one month after winning his third Indy 500. Andretti won the Formula One World Championship and is a three-time Sebring winner (he also won the 6-hour version of Daytona). Indianapolis 500 winner Johnny Rutherford once won one of the Daytona 500 qualifying races. In 2010, Chip Ganassi became the first car owner to win the Daytona and Indianapolis 500s in the same year, with Jamie McMurray winning the Daytona 500 and Dario Franchitti winning the Indianapolis 500.

In 2010, Bruton Smith (owner of Speedway Motorsports, Inc.), offered $20 million to any driver, IndyCar or NASCAR, who can win both the Indianapolis 500 and the Coca-Cola 600 on the same day starting in 2011, a feat that had never been accomplished. For 2011, the Indianapolis Motor Speedway moved the start time of the Indy 500 back to 12:15 PM EDT (prior to 2005, the engines started at 10:52 AM EST; under the modern schedule, engines start around 12:05 PM for a start around 12:15 PM), which re-opened the window for travel. Brad Keselowski suggested that he would consider answering the challenge in 2014. It was announced on March 4, 2014, that Kurt Busch would attempt to qualify for the 2014 Indianapolis 500, driving a fifth car for the Andretti Autosport team. Busch completed all 500 miles at Indy to finish sixth but dropped out of the 600 with a blown engine just past the 400-mile mark.

However, for 2019, NBC Sports and the Speedway changed the start time again. The engines are scheduled to start at 12:38 PM for a start time of 12:45 PM EDT.

Technical regulations


Technical specifications for the Indianapolis 500 are currently written by IndyCar. Rules are generally the same as every other IndyCar race. In the past, particularly during the era in which USAC sanctioned the Indy 500 (but CART sanctioned the other Indy car races), rules at Indy slightly differed at times. The result, for example, would be a particular chassis or engine configuration being legal at Indy, but not so at the CART-sanctioned events. This was rather commonplace in the 1980s and early 1990s, when "stock-block" engines (namely the V-6 Buick) was allotted an increased level of turbocharger boost by USAC at Indy, compared to the purpose-built V-8 quad-cam engines. While the "stock block" engines were technically legal in CART competition, they were not given the increased boost advantage, which effectively rendered them uncompetitive, and precluded their use by teams. The most famous manifestation of the USAC rules disparity was the Ilmor-built Mercedes-Benz 500I engine fielded by Roger Penske in 1994.

Teams may enter up to two machines under a given car number—the "primary" car and a "backup" car. The backup car is identified by the letter "T". For example, the two cars for the #2 team would be numbered #2 and #2T. Both cars may be practiced during the month, but due to engine lease rules, they must share the same engine. It is not uncommon for teams to prefer their backup car, if it is deemed faster, or for other strategic reasons. Additionally, as the month wears on, a "T car" may be split off into a separate entry, and reassigned a new number, or be sold to another team.

All cars must pass a rigorous technical inspection before receiving a sticker signifying that the car is eligible to practice. Various criteria include minimum weight, dimensions, and approved parts, particularly safety equipment. Before and after qualification attempts, cars must pass another inspection. The pre-qualifying inspection is focused on safety aspects and is done on the pit lane qualifying queue. It is relatively brief, due to the time constraints of the qualifying procedure. The post-qualifying inspection is much more stringent and lengthy, taking place in the garage area. It is to detect deviations from the performance guidelines set forth by the league, and cars can and have been fined or outright disqualified if they fail inspection.

Qualifying procedure


Throughout the years, the race has used several different qualifying procedures. The current four-lap (ten-mile) qualifying distance was first introduced in 1920 and has been used every year since 1939.

In 2019, the qualifying procedure was refined. "Bump Day" and "Pole Day" were moved the second day of qualifying and drivers who qualified in positions 10-30 will be locked into the field on day one. On the weekend before the race (Saturday and Sunday), all cars are entered into a blind draw for the qualifying order.


 * Saturday: All entries are guaranteed at least one attempt to qualify and can make additional attempts if time permits. At the end of the session, the fastest nine drivers advance to a "shootout" session held on the next day to determine pole position and the first three rows of the grid. As mentioned above, drivers who qualify 10th-30th have their spots locked in and will not re-qualify. Drivers who qualify 31st and lower advance to a separate "shootout" session also held on the next day to determine the final three spots on the grid.


 * Sunday: The drivers who qualified 31st and lower from Saturday have their original times erased. These drivers are then given only one attempt to re-qualify using the same four-lap format. Drivers who qualify 31st-33rd have their positions locked in. Drivers who finish 34th and lower fail to qualify. The fastest nine drivers from Saturday take part in the "Fast Nine Shootout". The qualifying order is based on the times from Saturday's session from slowest to fastest. Once again, the times from Saturday are erased and each driver is given only one attempt. The fastest driver wins the highly coveted pole position and the remaining eight drivers have their positions locked in based on their times.

For each attempt, cars are allowed two warm-up laps. At that time, a member of the team is stationed at the north end of the main stretch. He or she must wave a green flag, signaling an attempt, or else the car will be waved off. The attempt can be waved off during any of the four laps by the team, driver, or race officials. (The series will wave off the run if it is obvious the run will not be fast enough to qualify and it is getting late in the day.) If an attempt is waved off after the run starts, the attempt counts towards the three-attempt limit and the previous time is still forfeited unless race officials waved off the attempt because of weather.

Memorabilia
Many people promote and share information about the Indianapolis 500 and its memorabilia collecting. The National Indy 500 Collectors Club is an independent active organization that has been dedicated to supporting such activities. The organization was established January 1, 1985, in Indianapolis by its founder John Blazier and includes an experienced membership available for discussion and advice on Indy 500 memorabilia trading and Indy 500 questions in general.

The longest-running Indy racing memorabilia show is the National Auto Racing Memorabilia Show.

Entertainment
The Indianapolis 500 has been the subject of several films and has been referenced many times in television, movies, and other media.

Milk
Louis Meyer requested a glass of buttermilk after winning his second Indy 500 race in 1933. After winning his third title in 1936, he requested another glass but instead received a bottle. He was captured by a photographer in the act of swigging from the bottle while holding up three fingers to signify the third win. A local dairy company executive recognized the marketing opportunity in the image and, being unaware Meyer was drinking buttermilk, offered a bottle of milk to the winners of future races. Milk has been presented each year since then, apart from 1947 to 1955. Modern drivers are offered a choice of whole, 2%, and skim.

At the 1993 Indianapolis 500, winner Emerson Fittipaldi, who owned and operated an orange grove, notoriously drank orange juice instead of milk during the televised winner's interview. He eventually relented and also drank from the milk bottle later in the post-race ceremonies after the broadcast was over, but the public relations damage had already been done. The snub led to Fittipaldi being booed at the next ChampCar race, the Milwaukee Mile, in Milwaukee, Wisconsin, the heart of dairy country, and by some, as late as the 2008 Indianapolis 500 in which he drove the pace car. In the 2016 Indianapolis 500, as a promotion, the track gave out commemorative bottles of milk to 100,000 attendees to toast the winner with milk after the race.

Broadcasting
Radio coverage of the race dates back to 1922. The race has been broadcast live on the radio in its entirety by the Indianapolis Motor Speedway Radio Network since 1953.

The Hulmans did not allow live television coverage of the 500 until 1986, largely to maximize gate attendance. The race was briefly televised live in 1949 and 1950 on WFBM-TV (today's WRTV), after which the practice was discontinued. From 1964 to 1970, the race was broadcast live on closed-circuit television in theaters around the country. From 1965 through 1970, a highlighted version of the race was shown on ABC's Wide World of Sports. From 1971 through 1985, an edited same-day, tape delay broadcast of the race was shown in prime time. The race broadcast was edited down to either two or three hours in duration (including commercials).

From 1986 through 2018, ABC televised the race live in its entirety. However, at the request of the Speedway, Indianapolis affiliate WRTV was required to blackout the live broadcast and carry it on tape delay in prime time to encourage local race attendance; WRTV would air the ABC primetime lineup in the afternoon. In 2007 (the first year in which the race was carried under the ESPN on ABC branding), the race was first aired in high-definition. In 2016, the IMS declared a sell-out of race tickets for the 100th running of the event, meaning that WRTV would be allowed to air the race live for the first time since 1950.

Coverage of time trials on ABC dates back to 1961. ABC covered time trials in various live and in tape-delayed formats from 1961 to 2008 and from 2014 to 2018. ESPN (and later along with ESPN2) carried various portions of time trials from 1987 to 2008. Versus (now NBCSN) covered time trials from 2009 to 2013. Practice sessions have been streamed live online dating back to at least 2001.

In 2019, coverage of the Indianapolis 500 moved to NBC, as part of a new three-year contract that unifies the IndyCar Series' television rights with NBC Sports (the parent division of its current cable partner NBCSN), and replaces the package of five races broadcast by ABC with an eight-race package on NBC. The Indianapolis 500 is one of the eight races; this contract ended ABC's 54-year tenure as broadcaster of the race. WTHR is now the local broadcaster of the race under this contract; the existing blackout policy remains, though speedway officials have left the door open to allowing WTHR to air the race live in the event of a sellout.