The sound comes from the world of Pixar's Cars, first released in 2006, where Lightning McQueen is an ambitious young race car and Doc Hudson is the quiet former champion who mentors him in Radiator Springs. Engine noise is central to that story, so clips of motors revving and cars launching have long been reused by fans as shorthand for speed, competition and old-school racing spirit. On soundboards and in short videos, the McQueen and Doc pairing also carries nostalgia, letting creators signal a race, a challenge or a mentor moment without needing dialogue.