1966 Ford Mustang Mach 1 Concept

In late 1966, Ford designers prepared a Mustang concept to preview some of the design updates coming for the 1969 model. The Mustang Mach I was a two-seat fastback wîth a very aggressive lòòking chopped roof profile. Each of the rear pillars featured a flip-open racing-style gas cap while larger than normal air-scoops dominated the flanks. The sloped rear end included a hatchback, a feature that wouldn't appear on a production model until the 1974 Mustang II.
Several of the images show conceptual drawings. One of the images states a '427 engine prepared for SHOW with 4 double choke Weber carbs.' It goes on to say that the front 'hood raised by remote control and electric motors.' Another image showing the rear of the car stats 'trunk lid with spoiler acts as air brake : operates in 3 second cycle with two vacume service from Cougar.' It is clear from the drawings to the actual concept, some of the ideas were not implemented. Other design ideas that did make it onto the concept, such as the quad exhaust in the rear or the side mirrors located on the windows, did not make it onto production models.

Source - Ford