Jaguar XK120

Manufacturer	Jaguar Cars
Production	1948–1954 12,055 made
Predecessor	Jaguar SS100
Successor	Jaguar XK140
Class	Sports car
Body style	2-seat roadster (OTS) 2-seat coupé 2-seat Drop Head Coupé
Layout	FR layout
Engine	3.4 L XK I6
Wheelbase	102 in (2,591 mm)
Length	173 in (4,394 mm)
Width	61.5 in (1,562 mm)
Height	52.5 in (1,334 mm)

The XK120 was launched in roadster form at the 1948 London Motor Show as a testbed and show car for the new Jaguar XK engine. It caused a sensation, which persuaded Jaguar founder and design boss William Lyons to put it into production.

The "120" in its name referred to its 120 mph (193 km/h) top speed (faster with the windscreen removed), which made the XK120 the world's fastest standard production car at the time of its launch.

It was available in two 'open' versions – first as the roadster (designated OTS, for open two-seater, in America), then, also as a drophead coupé, DHC, from 1953 – and as a closed, or "fixed-head" coupé (FHC) from 1951. The DHC was a more deluxe open model, featuring the wood dashboard and wood accent veneers on the interior as found on the FHC.

The roadster version was successful in racing.

The Motor magazine road-tested an XK120 roadster in 1949. With hood and sidescreens in place, it achieved a top speed of 124.6 mph (200.5 km/h), accelerated from 0–60 mph (97 km/h) in 10.0 seconds and consumed fuel at the rate of 19.8 miles per imperial gallon (14.3 L/100 km; 16.5 mpg-US). The car as tested cost £1263 including taxes.

In May 1949, Jaguar demonstrated an XK120 roadster to the press on the high-speed autoroute between Jabbeke and Aeltre in Belgium. The road was closed for the occasion. The white left-hand drive car, chassis number 670002, was the second XK120 built. Jaguar's development engineer Walter Hassan was to have driven but fell ill, so Jaguar test-driver Ron "Soapy" Sutton substituted for him. With hood and sidescreens erected, and the airflow under the car improved by the addition of a full-length aluminium undertray, the Jaguar was timed through the flying mile by the Royal Automobile Club of Belgium at 126.448 mph (203.498 km/h). With hood, sidescreens and windscreen removed, a metal airflow deflector fitted in front of the driver, and a tonneau cover fastened over the passenger side of the cockpit the speed improved to 136.596 mph (219.830 km/h). The XK120 showed itself to be the fastest production car in the world.