Indianapolis 500 Centenary Countdown: Not 33 (times 3)

As we continue to count down to the 100th anniversary running of the Indianapolis 500 on May 29, 2011, we're wrapping up our look at the history of the 33-car starting field. Last week, we covered the winding – and often random – tale of that legendary number in the pre-World War II era. This week, we look at three often forgotten footnotes: the trio of post-war races in which a field other than 33 cars took the start.

1947 – 30 cars

Labor strife was a common issue as the country readjusted to civilian life after World War II, and the Speedway was not immune to this phenomenon.

Even before the 1946 “500,” drivers, owners and chief mechanics had formed an association, the American Society of Professional Auto Racing, or ASPAR, which gradually came into conflict over prize money levels with the American Automobile Association (AAA), the sanctioning body for most professional races, including Indy.

Even though the Indy 500's minimum purse had been increased from $60,000 to $75,000 for 1947 in response to ASPAR's demands, the association demanded more, under threat of a boycott. On the closing date for entries, only 19 had been submitted.

Emergency meetings in early May between Speedway owner Tony Hulman, track president Wilbur Shaw and ASPAR representatives led to a compromise in which late entries from ASPAR members were accepted – but with the proviso that no pre-entered cars could be bumped from the starting field by ASPAR cars.

All the delays had hurt the ASPAR teams' preparations, however, and by the close of official qualifying, only 17 cars had made the field. A special extra session enabled 28 cars to beat the minimum qualifying speed of 115mph, while two more cars were added on race morning. But, on race day, sixth-placed finisher Rex Mays was the only ASPAR driver in the top nine. (ABOVE: The 30-car field takes the start. Bottom left of the frame, movie legend Clark Gable watches them head to Turn 1.)

The association got some of what it wanted, as Hulman mailed out an extra $15,000 in prize money beyond the agreed amount. ASPAR, however, was never heard from again.

1979 – 35 cars

Another labor dispute led to a “supersized” starting field at Indy, but this time prize money was just part of a larger disagreement over the governance of the sport involving the United States Auto Club (USAC) – which had replaced the AAA as the sport's sanctioning body in 1956 – and Championship Auto Racing Teams (CART).

CART had started out as a lobbying group representing the car owners' interests within USAC. However, disagreements between the two parties led CART to sanction its own series of races in competition with USAC's for '79. The CART teams filed entries for the USAC-sanctioned Indy 500, but their entries were rejected since the teams were “not in good standing with USAC.” CART responded by filing an injunction in federal court to allow its teams and drivers to compete, which was granted.

The legal battles were not over, however. After qualifying, several owners whose cars had failed to make the 33-car field went to court, claiming they had not been given a fair chance. They charged that some qualified cars had made modifications to their exhaust systems that had overridden the effects of the “pop-off valve” that limited turbo boost pressure to mandated levels.

USAC offered a compromise: Any of the 11 non-qualified cars that could beat Roger McCluskey's 183.908mph bump speed in a special race day morning session would be allowed to start – briefly raising the specter of a 44-car field. Eight cars availed themselves of this opportunity, but two met the cutoff speed, increasing the starting field to 35 cars. One of them, Bill Vukovich, went on to finish eighth.

In the race itself, CART got the bragging rights in terms of results, with A.J. Foyt the only USAC stalwart to finish in the top six. The legendary Texan finished second behind some guy named Rick Mears taking his first Indy 500 win. (RIGHT: En route to victory, Mears' Penske-Cosworth PC-6 leads Danny Ongais' Parnelli-Cosworth, which finished fourth.)

In contrast to the ASPAR situation of 32 years earlier, however, CART would not fade away. Its teams continued to dominate while racing under an uneasy truce flag at Indy for the next 16 years.

1997 – 35 cars

The long-simmering relationship between CART and the Indianapolis Motor Speedway had finally collapsed in the mid-1990s, with Speedway president Tony George opting to run a new series of races in '96 under the Indy Racing League banner, which would include the Indy 500. CART teams were invited to participate, but chose to put on a rival race of their own rather than submit to the Speedway's stipulation that the top 25 cars in the IRL point standings would be guaranteed starting places in the Indy field.

The league's switch to normally aspirated engines and an all-new chassis formula for 1997 ensured that CART teams continued to stay away, and during the month of May it was announced that the controversial “25-8” rule would be rescinded. Consequently, it was decided that Lyn St. James and Johnny Unser – who had been among the fastest 33 qualifiers but, without guaranteed starting status, found themselves outside the field – would be allowed to start.

So, a year after the “split” that grew out of the original CART/USAC war of 1979, the field returned to a 35-car starting lineup as an unintended result.

• For tickets to the 100th Anniversary Indianapolis 500 on May 29, 2011, CLICK HERE.

For more insight on the history and heritage of the Indianapolis 500, check out legendary Indianapolis Motor Speedway historian Donald Davidson's blog HERE on Indianapolismotorspeedway.com.

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