The 4 ninja cars that intercept Tow Mater is a reference to the 2001 film "The Fast and the Furious"; their black paint, green neon under glow, and Honda Civic inspired design is nearly identical to the heavily modified, spoon-engined cars Dominic Toretto and his gang use.
Mike and Sulley, in their car forms, are seen briefly when Mater drifts through a Japanese restaurant, that is referring to Harryhausen's Sushi resturant