Fifty years ago, in the experimental
department of the Jaguar factory in Coventry, a new engine burst into life. It was the XK
engine and it was destined to power some of the most evocative cars of this century. It
was an engine which would speed Jaguar cars to five historic victories in the Le Mans
twenty four hour race. It was an engine which would power generations of luxury saloons.
It remained in production for over forty years and this year Jaguar will celebrate the
fiftieth anniversary of the birth of an engine which helped transform the company from an
ambitious but specialist car builder into one of the world's premier luxury manufacturers.
The first glimpse the motoring public had of the twin overhead camshaft XK engine was at
the London Motor Show, at Earls Court, in October 1 948. It was installed in the car which
was the undoubted star of the show - the Jaguar XK 120.
The XK story, though, had started some years earlier when Jaguar's founder, William Lyons,
had been on firewatch duty during the war. Together with his Chief Engineer, William
Heynes, and Claude Baily, he decided that Jaguar needed a powerful, refined new engine for
the generation of post war Jaguar cars he was planning. The XK engine would be the
first-ever engine designed by Jaguar's own engineers. William Lyons had previously used
adapted versions of other manufacturers' engines in his pre-war SS cars.
Heynes, Baily, Walter Hassan and cylinder
head specialist, Harry Weslake, worked on the new engine in the immediate post war years
at Jaguar's factory in Swallow Road, Coventry. Although originally designed in both four
and six cylinder versions, only the 3.4 litre, six cylinder engine would eventually go
into production. The two litre, four cylinder version though was listed in the original XK
catalogue and a prototype four cylinder XK engine powered Major A.T.G. 'Goldie' Gardner's
EX 135 streamliner to 175 mph on the Jabbeke Highway in Belgium in August 1948.
Hailed at the 1948 London Motor Show" the most beautiful production sports car in the
world", the XK120 quickly confirmed William Lyons' proud contention that it was also
the fastest production car in the world. The Jaguar boss conclusively demonstrated this in
1949 when he took a standard XK120 and a planeload of British motoring correspondents back
to Belgium's Jabbeke Highway. Driven by Jaguar's test driver, Ron 'Soapy' Sutton, the
XK120 covered the flying mile at 132.596 mph.
Performance credentials established, the Jaguar XK120 and its purpose-built racing
cousins, the XK-powered C-type and the D-Type, went on to score famous victories in races
and rallies in the UK, Europe and North America. Most memorable of all were the great wins
in the Le Mans twenty four hour endurance race in the 1950s. Jaguar C-Types were
victorious in 1951 and 1953 and then the D-Types gave Jaguar three more wins in 1955, 1956
In addition to dominating the race tracks in 1950s, the XK engine proved its versatility
by powering Jaguar's luxury saloons. The compact Mark 1 and Mark II saloons relied on XK
power as did the elegant, imposing Mark VII, Mark VIII and Mark IX saloons. And the
sporting successors to the original XK120 - the XK140, the rare and uncompromising D
Type-based XKSS and the XK150 - had XK engines under their bonnets.
Thirteen years after the original XK engine made its debut came a car which was destined
to become one of the greatest sports cars of all time. The Jaguar E-Type was launched at
the Geneva Motor Show in 1961 - immediately becoming an icon in its era. Under the long,
sensuous bonnet was the XK engine, now enlarged to 3.8 litres and giving enough power to
rocket this sensational car to 150 mph.
Whilst sports car enthusiasts savoured the performance of the XK engine in the E-Type,
businessmen around the world relaxed as the XK engine's refined power quietly propelled
their luxurious Jaguar Mark X limousines.
In 1964, the XK engine was again enlarged - to 4.2 litres - giving added power to the
sporting E-Type and even greater refinement for Jaguar's luxury saloons. Smaller capacity
versions of the engine though continued to be available for the 240 and 340 saloons and
the much admired S-Type saloon.
In 1968, exactly 20 years after the debut of the XK engine, came a new Jaguar saloon which
set new standards of style and refinement. The Jaguar XJ6 was immediately hailed as one of
the world's best luxury saloons with its combination of sports car performance and
handling, and limousine luxury.
From its launch in 1968 until the last XK powered XJ6 was built in 1986, this car remained
a benchmark for modern luxury saloon car design. Contemporaries of Sir William Lyons say
that the XJ6 was the car of which he was most proud and the last photograph taken of
Jaguar's founder shows him standing at the gates of his Warwickshire home alongside a
The last XK-engined Jaguar saloon - the Series 111 XJ6 - went out of production in 1986.
But XK engined cars were still available into 1990s. The stately Daimler limousine, which
was first introduced in 1968 had always relied on XK power and this imposing vehicle
continued to be built, in strictly limited quantities, until 1992.
The engine that was first conceived by Williams Lyons and his talented team of engineers
in the dark nights of the Coventry blitz, and was first unveiled to the public in 1948,
was installed in Jaguar and Daimler production cars for 44 years. It started its
distinguished service under the bonnet louvres of a high performance sports car. It ended
its historic 44 year production run in a limousine which is today used regularly by Her
Majesty Queen Elizabeth II.
Jaguar's Chairman and Chief Executive Nick Scheele said: "The XK engine was a
masterpiece of design and the car in which it was first installed, the Jaguar XK120, quite
clearly signposted the direction Jaguar would follow in the future. Few engines have made
such a profound mark on the history of the motor industry and it is a fitting legacy of
Sir William Lyons and his enormously talented team of engineers. It is wholly appropriate
that we celebrate the fiftieth anniversary of the XK in a year when we announce the latest
member of the Jaguar XK family, the Jaguar XKR powered by a supercharged version of
Jaguar's new AJ V8 engine. This car and this engine are in the finest traditions of Jaguar
and its proud engineering heritage."