For the true race car enthusiast, LeMans, after more than 30 years remains the most realistic racing movie ever made. Steve McQueen was a true sports car enthusiast and a racer himself, and he hired director John Frankenheimer to film him (Steve) in the world's most important sports car race -The 24 Hours of LeMans. Real factory race cars from Porsche and Ferrari were used to make the movie, and cameras were mounted in the cars during the race for much of the movie footage. The action was real, the crowds, the location.
The only thing lacking was a story, an afterthought hastily written after the movie was halfway through production. But still, much better than the scripts in more recent films like "Days of Thunder" and "Driven" where we are led to believe an inexperienced rookie (Tom Cruise) and a washed-up has been (Sly Stalone) can roll onto a race track without practice, break the track records, stick quarters to their tires at 160 mph, start CART race cars without starters and race through downtown Chicago at night without lights and not draw the attention of police, and then go out and beat the established champs in the race the next day.
Another old movie like LeMans, "Grand Prix" with James Garner was good. Real tracks like Monaco, real drivers in the background scenes, but the cars were mocked-up Formula 3 cars -not Formula 1, and you could tell. Get LeMans, and get Steve McQueen's "Bullet" for the epic streets of San Frabncisco car chase scene, one of the best chase scene ever (now only recently relegated to 2nd place by the chase scene in "Ronan").