Some shampoos cause a tingling sensation. Scalp tingling may occur as a result of an allergy to a hair product. Some people might also experience scalp tingling from excessive scalp picking and scratching. People who experience regular migraines often complain of a tingling scalp.
While a few of the buildings in Radiator Springs are exact replicas of landmarks along Route 66, most of the businesses populated and operated by the automotive characters in the movie are a pastiche of places found along the fading but still popular road.
Carburetor County Speedway was a racetrack found in Radiator Springs. It is shaped like an oval and has a square track with a dirt shortcut in the middle of it. The dirt track is dirt so it will slow you down. If you didn't know how to correctly traverse the shortcut, you'd find yourself behind the back. Otherwise you'd be better off just racing on the outer course.