With sales and critical approval of the Cobra series at its peak in the mid-Sixties, AC Motors and their US associate, Carl Shelby decided it was time to raise the standards a little, by introducing seven-litre engines into the series.

The first " super powerful" Cobra to see the light of day was the 427, causing a sensation by being classed the fastest road car in the UK for a time.

Despite that particular claim to fame, the 427 proved to be something of an anti-climax, with sales disappointing.

The poor showing of the 427 meant that it was back to the drawing board, with the next ( and last) model released under the present working relationship, the Shelby Cobra 428 Frua was released, without too much fanfare, in the Autumn of 1967.

This time around AC hired Frua, of  Turin Italy, to design their new model less spartan in design than those who came before it.
 

Frua, who had worked with AC on the 427, was commissioned by AC to produce twin body styles, a convertible version and an elegant fastback coupe and an equally smart convertible.

Throughout their long history, AC had meticulously maintained their tradition of producing only" two-seaters" and the Cobra 428 Frua was no exception, although this model sat on a  wheelbase six inches longer than the 427.

In an attempt to move dramatically up-market, Shelby and AC ordered that the 428s should provide the most luxurious trim and the latest in technical fittings.

Once again, the AC Cobra Shelby 428  Frua drew its power from a Ford  7014cc/428 cu in V8 engine,  matched to a three-speed automatic transmission, although anyone who still wanted the feel of the gearstick, could ask for a four-speed manual transmission to be fitted in its place.

Like its predecessor, the 427, the 428 Frue was overly powerful, with a tendency to drift on corners, when the gas pedal was firmly floored

As soon as the first glimpses of the 428 were made available, The motoring press were not slow to point out that the car bore more than a passing resemblance to the latest Maseratis- not surprising as Frua also enjoyed a strong working relationship with the Modena-based producer of luxury sports cars.

Production of the 428 began in October of 1966 with the last Cobra shell produced at Thames Ditton in late 1968 During these two years; total production capacity was centred solely upon the two big and beautiful 428 models.

While AC were never the most cold-blooded efficient concern when it came to producing cars, with the  Cobra 428 Frua was exceptionally ponderous.

The production process would begin with AC sending the rolling chassis to Frua's plant in Bologna Italy, where the Italian crew added the trimmed and painted body shells, after which the cars were returned the cars to the AC plant Thames Ditton for completion.

While the working partners expected this process to take time, it soon became evident that insufficient emphasis had been placed on Italy's anarchic working practices and ultra-sensitive working relationships with the labour unions.

These twin factors added to the other unforeseen but relatively minor hitches, meant that the few potential customers for the  AC 428 soon found out that delivery dates could not be depended on, while build quality was often questionable.

Although the 428 was fast, it retained most of the Cobra 427's handling quirks and little habits, while also carrying a price tag that made it much more expensive than all of its sector rivals, the  Aston Martin DB6, the Jensen Interceptor and even costing twice as much as the Jaguar E-Type.

All of these factors combined caused the AC 428 Frua to become increasingly less attractive to potentials buyers, with only 81 models produced until the model was discontinued in 1973.

Despite its shortcomings, for the auto purist, the AC 428 Frua was everything it purported to be, thanks to its exceptionally high standards of fitting and finish, performance, handling, workmanship and sheer aesthetic appeal.

AC succeeding in winding down the Sixties, thanks to the 428 fastback and convertible in just the way they entered it -with a flourish- despite not surviving too far into the Seventies.