In Pixar's Cars, Dinoco is the sponsor whose logo appears on The King's blue race car.
The King, whose real name is Strip Weathers, is a veteran Piston Cup champion and one of the most respected racers in the film. His light-blue car carries Dinoco branding, including the company's distinctive dinosaur logo. Dinoco is presented as a major fuel and racing brand in the Cars world.
Rust-eze is Lightning McQueen's sponsor, not The King's. The Piston Cup is the championship trophy, rather than a sponsor. Dale Earnhardt is a real NASCAR driver and inspired aspects of The King, but he is not the name printed on the fictional race car. Dinoco also appears in other Pixar films as an Easter egg.