"Days of Thunder" turns 30 this year, and to celebrate NASCAR put together a documentary about the making of the movie that brought stock-car racing to the big screen.

The film starred Tom Cruise as NASCAR rookie Cole Trickle. Cruise was introduced to racing by the late Paul Newman, himself a very competitive driver off screen. After co-starring in "The Color of Money," Newman put Cruise in sports cars, which led to Cruise meeting NASCAR team owner Rick Hendrick, who eventually let the actor test one of his race cars.

That test—and other conversations with NASCAR personalities—pushed Cruise to pitch a NASCAR movie to producers Don Simpson and Jerry Bruckheimer. Cruise and writer Robert Towne then attended races to research the story and characters. They also had to convince NASCAR boss Bill France Jr. to get onboard. 

Filming took place at several NASCAR races, including the 1990 Daytona 500. Filmmakers planned to enter camera-equipped cars (built and raced by Hendrick Motorsports) in races for additional footage, but that meant qualifying said cars just like any other entrant. The first time around, the car didn't make the field, but in a subsequent race, driver Bobby Hamilton did so well that Hendrick decided to strip out the cameras and let Hamilton race for real. He even led a few laps.

Actors did some of their own driving, and were even asked to flick on in-car cameras at 120 mph, Cary Elwes, who played Russ Wheeler, said. For exterior shots, the production team built its own camera car—a 1986 Chevrolet El Camino body mounted on a NASCAR Cup Car chassis that looked like it could have been the ancestor of Chevy's C8 Corvette development mule based on a Holden Commodore Ute.

"Days of Thunder" has achieved cult-classic status, inspiring current NASCAR driver Kyle Busch to produce his own spoof video, and even motivating coders to reconstruct a long-lost video game based on the movie.