The Mustang has been in production since 1964.
The Mustang is a sports/muscle car introduced by the Ford Motor Company in 1964 and still in production (as of December 2010). Its horsepower can be measured in terms of either crankshaft horsepower or wheel horsepower.
Crankshaft horsepower, often shortened to crank horsepower, is a measurement of the horsepower output of the engine taken at the crankshaft itself, which is physically positioned before the transmission. Because some horsepower loss occurs at the transmission, crankshaft horsepower is generally considered to be an accurate measurement of the engine itself, but not of the actual vehicle. It is typically acquired from engine testing.
Wheel horsepower is a measurement of how much horsepower is produced by the vehicle itself, taken from the wheels powered by the drivetrain. In a Mustang, this will always be the rear wheels. Wheel horsepower is widely considered to be an accurate measurement of the horsepower of the vehicle itself. It can be measured on a dyno.
Some car enthusiasts have attempted to derive a standardized formula for converting crankshaft horsepower estimates to wheel horsepower estimates and vice versa. This conversion is based on horsepower ratings, drivetrain and transmission but is only an estimate of horsepower. The most accurate way to determine the horsepower output of a Mustang is to take it in for professional testing.