The 1981 Michigan 500, the inaugural running of the event, was held at the Michigan International Speedway in Brooklyn, Michigan, on Saturday, July 25, 1981. Branded as the 1981 Norton Michigan 500 for sponsorship reasons, the event was race number 5 of 11 in the 1981 CART PPG Indy Car World Series. The race was won by Pancho Carter - his first Indy Car victory. The race commenced a 20-year history of the Michigan 500 being a part of Indy car racing's Triple Crown.
Background
Indy car racing's Triple Crown began in 1971 when Pocono Raceway opened and held their inaugural Pocono 500, joining the Indianapolis 500 and California 500. This continued for 10 years until late 1980, Ontario Motor Speedway closed and created a void in the Triple Crown where only two 500 mile races would be held.
In 1979, Championship Auto Racing Teams was created as a way for Indy car teams to have greater control over the sport. It led to a split between CART and USAC, where two separate open-wheel schedules were held. In 1980, the two series briefly merged as the Championship Racing League before once again splitting. As Indy car racing entered 1981, USAC retained sanctioning control of the Indianapolis 500 and Pocono 500.
For the majority of the first twelve years of Michigan International Speedway, the July Indy car race was a 200-mile event. On February 26, 1981, track-owner Roger Penske announced that the race would be extended to 500 miles.
With NBC providing live coverage, the Michigan 500 would become the second 500-mile auto race to be aired live in its entirety, joining NASCAR's Daytona 500. At the time of the announcement, NBC's vice-president of sports programming, Dick Auerbach, said, "With the squabbles they've been having at Indianapolis recently, I think this race will be the 500-mile race of the future. It could supplant the Memorial Day race within a few years."
Penske insisted the creation of the Michigan 500 was not an attempt for CART to supplant the Indianapolis 500, but rather just a chance to build a successful event. "We have the finest racing facility in the country today. With the proper presentation we can build this to be a major event. It's a good business decision. We have no conflict with Indy."
Crowd enthusiasm was very high for the change in distance to 500 miles. Penske declared that ticket sales had almost doubled compared to the 200 mile event in July 1980. "The moment we announced we were going to have a 500-mile Indy car race here, it was like I had invented a new formula. The ticket sales jumped almost 100 percent over last year."
Bobby Unser won the 1981 Indianapolis 500 for Team Penske but had his win stripped away due to a rules violation and given to Mario Andretti. While the win was returned to Unser through a USAC appeal in October, as of July's Michigan 500, Andretti was still considered the winner of that year's Indianapolis 500.
USAC's Pocono 500 was held in June and was won by A. J. Foyt. CART teams boycotted the event and the field was filled with dirt cars. Tom Sneva, Dick Simon, Roger Rager, Jim McElreath, Tom Bigelow, Geoff Brabham, and Dean Vetrock were suspended by CART for 60 days for competing in the Pocono 500, a suspension that would extend through the Michigan 500. The drivers filed a lawsuit against CART in United States District Court for the Northern District of Georgia which was successful and overturned their suspension, allowing them to enter the Michigan 500.
After not committing to join CART for two years, A. J. Foyt obtained CART membership on July 13, and entered the Michigan 500. Mario Andretti skipped the Michigan 500 in order to run the 1981 British Grand Prix.
Practice and Time Trials
In Wednesday's opening three-hour practice, Johnny Rutherford and Tom Sneva posted the fastest practice speed when they ran identical lap speeds of 197.8 mph. Team Penske drivers Rick Mears and Bill Alsup ran laps at 196.7 mph, followed by Pancho Carter at 196 mph.
The opening round of Time Trials was held on Thursday afternoon. Tom Sneva won the pole with a speed of 201.359 mph. Johnny Rutherford and Rick Mears posted the second and third fastest speeds to occupy spots on the front row.
Salt Walther led second day qualifiers on Friday with a speed of 193.876 mph.
On Saturday, July 19, Roger Penske exercised his "promoter's option" and expanded the starting field to 37 starters. Two alternate starters and the top-two finishers from a 10-lap qualifying race were added.