In spite of the car´s bulk, it was not slow with a top speed of 120 mph, and it certainly appealed to Americans with the US and Canadian dealers placing orders worth 63 million dollars (£22.5m). Unfortunately the model did not turn out to be quite as successful as hoped, though gradually it matured into an excellent vehicle capable of transporting four or five people quickly and in great comfort.

Three E-types were privately entered for Le Mans in 1962. One retired but the Briggs Cunningham entry, driven by Briggs and Roy Salvadori, finished a highly creditable fourth followed by the Peter Lumsden/Peter Sargent E-type one place behind.

Meanwhile E-types had been clocking up a number of successes around the world and one car, entered by Jaguar dealer John Coombs, was being increasingly developed. The success of the E-types inspired Ferrari to build the 250 GTO and this led Jaguar to counter with a special racing version of the E-type, developed from the Coombs car.

Generally known as the ´Lightweight E´, these cars, of which just 12 were built, had an aluminium monocoque body and engines with a block of the same material. With fuel-injected, dry sump engines, considerably stiffened suspension and wider wheels, they posed a genuine threat to the Ferraris and beat them on a number of occasions.

In 1963 Cunningham took three Lightweight E´s to Le Mans. Unfortunately one retired with gearbox problems, the second crashed heavily after hitting an oil patch at 170 mph on Mulsanne and the third only managed to finish ninth after a long pit stop to repair a badly damaged bonnet.

Also in 1963 the S-type saloon car was announced. This was a pleasing compromise between the Mark II and the Mark X in shape. Most importantly the S-type was given independent rear suspension and the S-type was offered with either the 3.4 or 3.8 litre engine.

Two ´Lightweight Es´ were entered for Le Mans in 1964. Sadly, both cars retired with mechanical problems. To improve torque, the E-type was given a new 4.2 litre XK engine and synchromesh gearbox. Braking was improved by the deletion of the Kelsey Hayes bellows-type servo in favour of a Lockheed vacuum booster.

Internally the 4.2 E-types were given far better seats. The aluminium dash panels and centre consoles were now covered in black leathercloth. Like the Mark X, the only external way of distinguishing the 4.2 E-types was by the badge upon the bootlid.

Sir William Lyons had felt for some time that the company needed a four seater ´sports car´. In 1966 this was achieved by lengthening the E-type and adding a pair of small seats in the rear, so that the car could ´extend dad´s youth for another seven years´ as Motor put it.

The new car, known as the 2+2, was not to everybody´s liking but certainly made a more practical machine. Performance was not helped by the extra weight and frontal area. Top speed was now down to 136 mph. Price, as ever, was very competitive at £2,385 and a very healthy number were sold with, like all E-type production, the vast majority crossing the Atlantic to the States.

The 420 saloon was introduced in 1966. This was akin to a revised S-type with the Mark X frontal styling treatment. Offered, as the name implied, with the 4.2 litre engine, the 420 was an excellent car. It was, though, a stopgap model for Lyons and Knight who were working on something very special which would appear in a couple of years time.

For many years Jaguar had been Britain´s top dollar earner and, the most popular imported car in the States. By 1966 Jaguar´s post-war exports totalled £200m. A year later the Mark IIs metamorphosed into 240s and 340s. The models, now near to the end of their lives, were rejuvenated by a few minor trim changes and the 3.8 model was dropped from the range.

From time to time Jaguar´s thoughts had turned to competition and Sayer had wanted to build a mid-engined car. Heynes and colleagues had realised that if Jaguar was to remain competitive it would need to design a completely new engine, preferably of 12 cylinders.

In 1965, with the Lightweight E-types uncompetitive, a small team including Sayer and Mike Kimberley, later to head Lotus Cars, drew up plans for a mid-engined sports racing car. To power it, they designed a four cam V12 of 5 litres.

The car, the XJ13, was built in great secrecy in 1966 but there was an unfortunate lack of urgency about the project. It was eventually run in 1967. Sadly it was never to race and has become a museum piece for enthusiasts.

The shape was another Sayer masterpiece. Of obvious ancestry, it was one of the most beautiful cars ever conceived, and a lasting tribute to this brilliant man who prematurely died in 1970.

In 1968 the E-types underwent changes dictated by the US Federal Regulations.

With a less clean shape and increasing weight, the E-type was in need of another boost both in terms of prestige and performance. Jaguar were working on the answer and it had rather more than six cylinders.