Background
When AC launched the 100mph Ace in 1953, with a Tojeiro-designed twin-tube chassis, transverse-leaf independent suspension and its own engine dating back to 1920, they could hardly have imagined it would spawn a 7-litre fire-breathing monster – the world’s fastest production car in 1965 – with 485bhp and a top speed of 185mph in the competition model. Even less could they have dreamed that, almost 70 years on from the original Ace and 55 years since the Cobra 427 was introduced, the car was still so revered that numerous superb reproductions continue to be available, with enthusiasts slaving for years to build them to superb standards.
US racer and Le Mans winner Carroll Shelby was the catalyst for the Cobra. Retired from racing in 1960, he wanted to build a sports car, and approached several British manufacturers offering a partnership deal. AC had just lost their top performance engine, the Bristol straight six, so his suggestion of putting a light but powerful US V8 in an uprated Ace chassis hit the right note at the right time. Ford was keen to see a Ford-engined sports car beating Corvettes on the track, so they were more than happy to supply crated new small-block V8s – 3.6-litre at first, then 4.3, then 4.7, the classic 289. AC adopted the Salisbury rear axle used by the Jaguar E-type (but with outboard disc brakes), and in 1962 changed from a vague steering box to precise rack and pinion. AC built complete cars less engine and gearbox, and shipped them out to Shelby who completed them with new Ford components.
Shelby’s racing team soon had Cobras running rings round other machinery on US circuits, and as ever there was a demand for more power. AC realised the Ace’s chassis couldn’t take any more, so it was redesigned with 4in main tubes instead of 3in, and coil spring suspension all round. Wheelarches were massively flared to accept huge wheels and tyres, to help transmit the immense power of the big block V8 engine: the legendary 427 – the AC Cobra MkIII – was born.
By the time the 427 was in production, Carroll Shelby was preoccupied with Ford’s GT40 competition programme. The 427 missed homologation for 1965 and proved hard to sell: by the late 1960s, it looked expensive and outdated, despite its phenomenal performance. Just 312 road and race 427s were built, the last sold in 1968: AC, and Shelby, moved on.
But the Cobra shape was never forgotten, and it was not long before replicas started to appear – some just aping the shape but with mundane (or wildly different) running gear, others staying truer to the original design. In 1980 AutoKraft revived the 289, producing a high quality replica and in 1986 buying AC cars. Ford joined forces in 1987 and the AC Cobra MkIV was born. Production has continued, in very small numbers and with several changes of ownership, to this day, with either aluminium or composite bodies.
Of the many Cobra replicas around, the longest-lived and most popular has undoubtedly been the Dax, and it remains available to this day from the company’s North Weald, Essex base – though since 2017 Dax has been owned by enthusiastic Belgian Dax importer John Kox, under his JK Sportscars banner. Dax started, as DJ Sportscars, in 1968 and was the first company to make an AC Cobra replica kit. John Tojeiro, designer of the original Ace chassis, was a director in the 1970s and the decades of refinement that Dax has built into its Cobras shows through in their quality, from the smoothness of the glassfibre mouldings to the details of the construction and parts sourcing.



