Before it was Jaguar, it was 'S.S', and before that, it was the Swallow Sidecar & Coachbuilding Company of Blackpool, England, founded by William Walmsley. Initially, they built sidecars for motorcycles, adding automobile coachbuilding in 1926 using the popular and inexpensive Austin 7 chassis as their platform. The design had been created by Walmsley's partner, one William Lyons. Soon after, the company relocated to Coventry and the Swallow range grew to include models on the Standard Sixteen, Wolseley Hornet, and Morris Cowley chassis. Official marque status arrived in October of 1931 with the introduction of the S.S.I.
The 'S.S.' of the S.S.I represented 'Standard Swallow' (the 'Sidecar' had been dropped from the name in 1927 when it became the Swallow Coachbuilding Company) and the chassis was supplied by Standard, who also provided the four-speed gearbox and the six-cylinder side-valve engine. 2-liter or 2.5-liter displacements were available, while the SS2 came with a four-cylinder 1-liter side-valve engine. Body styles included a coupe or tourer, with a saloon being added in 1934 when the chassis grew two inches wider.
The S.S. 90 sports car was added to the lineup in 1935 and by this point in history, William Walmsley had recently retired and William Heynes had joined as Chief Engineer. The S.S.90 rested on a shortened S.S.I. chassis, re-engineered by Heynes and wore bodies styled by Lyons characterized by flowing lines, cut-away doors, a truncated tail, and a long bonnet. The '90' in the car's name represented its top speed of 90 mph.
Harry Weslake was described as England's greatest expert on cylinder head design. He built an enviable reputation that included working with W.O. Bentley tuning his racing engines cylinder heads, which resulted in the first Le Mans victory. He worked with Automotive Engineering for nearly a decade before setting up his own business in 1935 called Weslake & Taylor. This consultation business collaborated with companies such as Citroen, MG, Austin, and Swallow Sidecars. His work for Swallows included modifying the side valve Standard engine to overhead valves, and when equipped with twin SU carburetors, the 2,663cc Standard six produced 104 horsepower. Installed in the 8-foot 8-inch wheelbase chassis of the S.S.100 was a 'proper' sports car, although marketed as primarily for competition work. The engine grew larger in 1938, to a 3½ liter displacement size and power increased to 125 bhp. The four-speed gearbox had synchromesh on the top 3 ratios. They left the factory with 5.50 or 5.25 x 18-inch tires on 18-inch wheels, and brakes were by Girling.
As the popularity and production of the SS cars had increased, the company's ash-framed construction had become too time-consuming. All-steel bodies were adopted for the volume-selling saloon cars for 1938, and these heavier bodies required more power. Thus, the 2½-liter engine grew to the 3½-liter displacement. boosting output to 125 bhp.
The name '100' suggested 100 mph but period road tests revealed a top speed of 95 mph with the 2.5-liter engine and a zero-to-sixty mph time of 13.5 seconds. The larger 3.5-liter powerplant gave the S.S.100 a 100 mph top speed (its best recorded time was 101 mph) and a zero-to-sixty mph time of 10.4 seconds.
In 1936, the S.S.100 driven by Tommy Wisdom won the International Alpine Trial, the first of many competition successes, including class victories in the RAC events of 1937 and 1938, and the Alpine (outright) again in 1948.
Production of the S.S.100 continued until the outbreak of World War II in Europe, by which point around 198 examples of the 2½-Litre and 116 of the later 3½-Litre cars had been built. The '100' was in reference to its theoretical 100 mph maximum top speed. In March 1945 the S. S. Cars shareholders agreed to change the name to Jaguar Cars Limited. Jaguar would continue to use the vehicle's top speed as part of its model naming scheme, including the legendary XK120.
The introduction of the OHV unit was considered to justify the adoption of a new name for the series. Lyons later recalled 'I immediately pounced on Jaguar as it had an exciting sound to me.' ('Jaguar' would be adopted as the marque name in 1943, 'S.S.' having by then acquired a somewhat tarnished reputation). The SS100 was the first vehicle from Sir William Lyon's stable to wear the famous Jaguar 'leaper,' the marque's feline bonnet ornament in mid-1936. Another example wore a revised Jaguar 'leaper' in early 1937, mounted on the radiator cap. This second 'leaper' was the one that would later become the trademark for Jaguar Cars, Ltd.
by Dan Vaughan