A 50 50 is short for
Five O driving a 5.0.
Many police forces in the United States employ the use of marked and unmarked Ford Mustang police cars with powerful, sport tuned, high-horsepower, V-8 engines, commonly known as the Mustang 5.0 (Pronounced
five point oh), or Mustang GT.
The purpose of these vehicles is two-fold. Mainly to catch unsuspecting
speeders who might ordinarily recognize a typical unmarked police vehicle such as a Chevrolet Impala or
Ford Crown Victoria.
A secondary, less frequent use of the Mustang 5.0 is to give a police force vehicles suitable for use during high speed chases with motorcycles, exotic sports cars, or modified vehicles. Ordinary patrol cars are not capable of attaining the high speeds sometimes encountered during chases with the aforementioned vehicles. These ultra-high speed chases can sometimes reach 150 mph, or more!