To defeat Chevrolet, Ford needed a brand new car, a car with a sporty image and sporty actions, a car to be wanted by the young people." (Lublink).
There were actually two mustang prototypes; Mustang I, and Mustang II. It was Mustang II (built on the Ford Falcon platform) that caused the most commotion amongst potential buyers according to Ford. With the encouraging response ford received from the general public it set out to put the Mustang on car dealership sales floors by April of 1964. With the commercial airing just one day before the glorified release date of the mustang, Ford managed to sell a whopping 22,000 models of the mustang on its first day; which considering the time in age, and the potential buyers in proportion to today, these numbers are exceptional. The Mustang was the car of cars to have amongst young buyers during the middle of the sixties. .
The original pony car (as the Mustang was nicknamed) performed so well for Ford in sales that the following year the original 170 horsepower V6 engine, and the 260 horsepower V8 engines were dropped and replaced with 200 hp V6 engines, and 289 hp V8 engines. During 1965 the Mustang also received a performance touchup with the introduction of the Shelby line; which put out a performance mustang with a supercharged 400 hp engine a year later in 1966. By 1966, and with only roughly 2 years in production, Ford built the one millionth Mustang for sale. For Ford, selling so many Mustangs in such a short period of time was the proof that they needed to assure themselves that the Mustang had been an instant and powerful hit amongst buyers out in their market. .
Now in 1967, and with great expectations, Ford continued to bombard the public with the Mustang. In 1967 the Mustang grew two inches in length, allowing for a larger engine compartment, let the competition out there, especially the Chevrolet Camaro, that the Mustang was serious business.