Heresy! If you want a motor racing film with no story whatsoever watch Le Mans. It's still fantastic though.I watched Grand Prix (1966) earlier this week. the old cars were great, seeing the old tracks was even better, the rest of the film was dull as dishwater, which wasn't helped by the 3 hour run time or James Garners wooden acting.
By all means watch it for the racing, just fast forward through the tedious back story.
In orrder of awefulness