NASCAR driver Greg Sacks did most of Tom Cruise's stunt driving. Cruise wanted to do his own stunt driving, but wasn't allowed to for insurance reasons. The Chevrolets were prepared by Rick Hendrick's racing team, which later used some of the movie cars in real races. 35 cars were wrecked during filming.
The scene where Tim approaches Harry on a tractor was filmed on NASCAR legend Junior Johnson's farm.
The scene where Cole and Rowdy race rental cars on the beach shows birds scattering out of the way. The birds were lured onto the beach by birdseed, and in the first take most of them were run over.
All cars used in the movie for the races had to pass inspection and qualify. Bobby Hamilton qualified one of the movie cars in the top ten; they removed the cameras and he was allowed to enter the race.
Tom Cruise and Robert Duvall's characters are (very) loosely based on former driver Tim Richmond and his crew chief Harry Hyde. Richmond was known as an overnight sensation, and Hyde was the veteran crew chief. The scene where Duvall's character teaches Cruise about tire management is based on an actual incident between Hyde and Richmond. Tim Richmond died of AIDS complications the year before the film was released.
The scene where Cole Trickle leaves the pits after a race to hit Russ Wheeler is also based on an actual event during the 1987 all-star race at Charlotte, NC between Driver Bill Elliot and Dale Earnhardt.
In an effort to give a more realistic movie, existing broadcasters were brought in to provide the broadcast reporters and track announcers. Key among these were members of ESPN's racing crew, including booth announcer Bob Jenkins and pit reporter Dr. Jerry Punch.
Some footage for the movie was shot during the 1990 Daytona 500. Two additional cars, driven by Bobby Hamilton and Tommy Ellis, were added to the rear of the field for the purpose of filming them. These cars were not officially scored and left the race track after 100 miles (40 laps) were completed.
Cars designed specifically for the movie officially raced at Phoenix and Darlington, with Greg Sacks driving Cole Trickle's City Chevrolet car in both races. Bobby Hamilton drove Rowdy Burns' Exxon car at Phoenix, while Hut Stricklin drove it at Darlington. None of the cars finished their races, but Hamilton did lead 5 laps in his before an engine failure.
During the Darlington race in which the two movie cars appeared in, Neil Bonnett, one of the drivers interviewed at Daytona before the race, was nearly killed in a serious accident.
In the beginning of the film, the announcer introduces driver Aldo Bennedetti from Reading, Pennsylvania. This character is most likely a reference to real-life driver Mario Andretti. Both are of Italian descent, Mario's brother is named Aldo, and Mario is from Nazareth, Pennsylvania.
City Chevrolet, a sponsor for Cole Trickle early in the movie, is a real-life Charlotte area dealership that is owned by Rick Hendrick, who prepared most of the cars in the movie.
**This is the item I find fascinating.
According to an article in Car and Driver by Bob Zeller, Bobby Hamilton was paid about $14,000 to $15,000 by Rick Hendrick to come drive the camera car. At the time, Bobby Hamilton was making about $185 a week driving a wrecker (tow truck). He did so well, Rick Hendrick hired him on for the next NASCAR race in Phoenix and the rest of the reason.
Production began without a finished script; scenes were often written the day of filming. During one driving sequence, Tom Cruise actually had to read his lines off cue cards attached to his windshield, which resulted in a minor car accident. For subsequent driving sequences, Cruise was fitted with a special earpiece to have lines fed to him.
Most of the cars used in this film were actually Chevrolets outfitted with special fiberglass bodies made to resemble stock cars. The vehicles routinely broke down from the strain of the racing or had their bodies greatly damaged. At one point, half the fleet was in the repair shop.