Birth of the AC 428
With Ford taking an increasingly large role in the slow-selling Shelby Cobra, and both Ford and Carroll Shelby moving on to other projects, AC decided to adapt their existing MkIII chassis to create a new vehicle under their own control.
In search of a carrozzeria to produce a body for the car, the Hurlocks first went to Bertone, then to Frua at the suggestion of Hubert Patthey, the Swiss importer of AC cars.
The body delivered by Frua is very similar in appearance to the Maserati Mistral, also styled by Frua. The two cars share the front quarter windows and door handles. The bumpers and windscreen may also be shared.
The first prototype, designated CF 1, had an unmodified MkIII suspension, and a removable metal tonneau cover behind the seats under which the hood was stored. The original engine in this car was a Ford 390 V8, later replaced by a Ford "428" V8. CF 1 is reported to have had a light alloy body, although one reference reports that CF 1 had a steel body with aluminium bonnet and door skins. Production cars also had side vents added to the wings to exhaust hot air from the engine bay.
For production cars, AC replaced the Cobra MkIII's competition-oriented suspension's spherical-joints with Metalastik bushings.
AC's new car was first seen in drophead coupé form at the 1965 Earls Court motor show as the AC 427. AC's earliest advertising for the car also used the AC 427 name. Only two cars were built with the Ford "427" engine.
By mid-1966, the AC 428 became available. A fastback coupé version debuted at Earls Court in 1967.
Derek Hurlock is on record as saying "I like the 428 because it fits my image of a true GT Car." He also said "Like anything exclusive, especially from craftsmen, it costs a lot of money. For this you get one of the fastest cars on the road, guaranteed to make an impression anywhere, and backed by a small company that cares. This one AC that joined that select company of very fast, very luxurious touring automobiles which moved effortlessly from current model to collector's piece."
The cars were built to rolling chassis condition at AC's plant in Thames Ditton, England, then shipped to Frua's workshop in Turin, Italy to have the body fitted, then sent back to England to have the powertrain and trim added. Production costs were high, and the cars could not be sold at a profitable price.
