Jaguar SS Jaguar 100

SS Jaguar 100 at a glance

From Swallow Sidecar to SS Jaguar

The company behind the car began in 1922 as Swallow Sidecar, founded by William Walmsley and William Lyons. The SS name dates from 1934 and kept the link with the Swallow Sidecar origins. In 1935 the name "Jaguar" was first given to an SS saloon and then to all new SS models. In March 1945 the shareholders agreed to rename the company Jaguar Cars Limited.

The firm's own history page fills in the steps. Swallow made motorcycle sidecars in Cocker Street, Blackpool, and then coachbuilt bodies on Austin, Morris, Standard, Fiat and Wolseley Hornet chassis. In the winter of 1928–1929 it moved to a former munitions factory at Foleshill, Coventry. In 1929 Lyons and John Black of the Standard Motor Company built a one-off boat-tailed two-seater, the "First SS". The SS 1 was shown at the Motor Show in October 1931, and the SS 1 and SS 2 went on sale in 1932 with Standard engines and chassis.

The direct forerunner was the SS 90 of March 1935, the company's first open two-seater sports car. It used the 2½-litre side-valve six in a shortened SS 1 chassis and was named after a claimed top speed of 90 mph (145 km/h); only 23 were made. The SS 100 was introduced in 1936 as the "SS Jaguar 2½ Litre 100 Model". Its chassis was a shortened version of the frame designed for the 2½-litre saloon and first seen on the SS 90 of 1935. Our article on Swallow Sidecars and SS Cars tells the company's early history in detail.

Engine: the Standard six with a new head

The engine started life as the 2½-litre side-valve six from the Standard Motor Company. For SS it was converted to overhead valves with a new cylinder head designed by William Heynes and Harry Weslake, and twin SU carburettors were bolted directly to the head. The output rose from about 52 kW (70 bhp) in side-valve form to 70 kW (100 bhp); the SS Cars article credits Weslake's head with 76 kW (102 bhp). Lyons had hired Heynes as chief engineer from Hillman, where he had come from Humber, and Weslake for engine tuning. Standard manufactured the new head for SS and also supplied the engines and chassis, while Swallow styled the bodies.

With about 1,150 kg, the 3½-litre car had about 81 kW per tonne, against about 61 kW per tonne for the 2½-litre. That is a difference of 23 kW for an engine 822 cc larger; the power-to-weight calculator puts the figure next to modern sports cars.

Chassis and performance

The chassis was simple even for the 1930s: rigid axles at both ends on half-elliptic leaf springs, Girling brakes and 18-inch wire wheels with 5.50 or 5.25 × 18 tyres. The four-speed gearbox had synchromesh on the top three ratios. The wheelbase was only 2,642 mm and the length 3,886 mm.

The SS Cars article gives the company's own claims for the SS 100 as 160 km/h (100 mph) and 0–60 mph in 11 seconds. Autocar tested both versions in 1937:

The 3½-litre car therefore justified its name. Some chassis were sold to outside coachbuilders, but almost all cars carried the factory two-seater body.

The leaper and notable cars

The first Jaguar "leaper" mascot was shown on an SS 100 in the middle of 1936, in a design described by William Lyons. A revised leaper on the radiator cap of the car registered CKV 250, photographed early in 1937, became the company's trademark. CKV 250 was ordered as a gift for the young King Mihai I of Romania, who reportedly drove it until he was forced out by the communists.

Other cars have their own stories. The politician Alan Clark owned an SS 100. CNP 947 was raced in the USA by the broadcaster Dave Garroway; it has alligator-hide trim and a 3.8-litre XK engine supplied by Jaguar. A 1937 3½-litre roadster won at Pebble Beach before it was sold at auction in 2010. Auction prices for the SS 100 are quoted by the sources in pounds sterling, so they are not given here.

Replicas

The SS 100's looks and rarity have led to several replica series:

A Finch car has won the Australian Concours d'Elegance. Because the replicas use different running gear, the chassis number and engine are the first things to check on any car offered as an original.