Singer SM Roadster
| Industry | Automotive |
|---|---|
| Products | Singer Roadster (car model) |
The Singer Roadster was a sporty open 2/4-seater tourer with nine tax horsepower, produced by Singer Motors between 1939 and 1955. Introduced in March 1939 as an open variant of Singer's Bantam saloon, it shared numerous components with the Bantam model.
Manufacturing was halted throughout World War II but recommenced afterward, featuring a forward-shifted engine to enlarge cabin space along with several other enhancements. In 1949, the Roadster evolved into the 4A version, which included a four-speed manual transmission. Later brief iterations comprised the 4AB and 4AC models released in 1950, followed by the 4AD SM Roadster in 1951. Competing with the MG T series, the Roadster was recognized for its stylish appearance. Production ceased in 1955. Additionally, a small number of bodies were custom-built by James Young.
Singer 9 Roadster 1939-1949
The initial Roadster was a two-door touring car with occasional seating for four, mainly based on the Bantam saloon. It housed Singer’s overhead camshaft inline-four engine of 1074 cc capacity, fine-tuned to produce power at 5000 rpm through a highly efficient "hot-spot" manifold paired with a downdraught SU carburettor, and featured slightly increased compression.
In 1940, sliding glass panels replaced the earlier celluloid side screens, while a chromed front bumper became standard equipment along with twin aero screens that allowed the windscreen to fold down. A custom-fitted suitcase was designed to optimize luggage capacity. The vehicle’s performance was limited by the Bantam’s three-speed gearbox, resulting in a maximum speed near .
Advertising materials alluded to inspiration drawn from the Singer Nine#Le Mans model but deliberately distanced itself from direct racing associations following the fatal Ulster TT incident in 1936. The Roadster aimed to offer an affordable sports car alternative.
Singer advertised a top speed of , with acceleration from zero to mph achieved in six seconds and reaching mph within eighteen seconds. Standard features comprised a spring steering wheel, concealed spare tire, a 12-volt electrical system, and windscreen wipers.
The body construction utilized traditional aluminum panels mounted over wooden frames. Suspension was based on leaf springs combined with rigid axles both front and rear; braking was mechanically actuated.
Post-war production restarted in 1946 incorporating upgrades such as non-lubricated rubber shackle bushes, repositioning of the engine to improve seating comfort, and an enhanced rear lid that created a flat luggage surface. These modifications contributed to better handling and ride quality through improved engine mounting and isolation. Production largely focused on export markets; the Roadster found favor among Indian aristocracy and Maharajas.
Singer 9 Roadster series 4A 1949-1950
The 4A version debuted in September 1949, enhancing the Roadster by adopting the four-speed gearbox from the Singer Hunter. The original SU carburettor was replaced by a Solex unit, which boosted power output by one horsepower. The driver’s seating position was modified for easier ingress and egress, while relocating the gearbox improved what had been an awkward gearshift mechanism. Additionally, bumpers were redesigned to be larger, more robust, and featured rounded ends.
Singer 9 Roadster series 4AB and 4AC 1950-1953
Introduced in October 1950, the 4AB model incorporated notable technical advancements such as independent front suspension utilizing coil springs and a combined "hydro-mechanical" braking system developed by Girling. Visually, it featured a shortened hood with fixed side panels, disc wheels, and redesigned fenders that were more rounded and deeper in profile. The steering box was relocated to a central position within the chassis, facilitating streamlined manufacturing for both right-hand and left-hand drive versions. Production of the 4AB continued alongside the larger 4AD until January 1953.
The limited-production 4AC prototype was equipped with a larger 1194 cc engine, which was essentially a down-sleeved variant of the 1.5-litre powerplant from the Singer SM1500, reflecting Singer's initiative to streamline its range of models.
Singer SM Roadster series 4AD 1½-litre 1951-1955
The last iteration of the Roadster, known officially as the Singer SM Roadster and designated 4AD, made its debut at the October 1951 Paris Motor Show as an export-exclusive model. It retained the chassis and body design while incorporating the 1497 cc engine producing 48 bhp from the SM1500 saloon, along with the hybrid hydraulic/mechanical brake setup. Starting in 1953, an upgraded engine option featuring twin carburettors delivering 58 bhp became available. The 4AD can be identified by its larger, more rounded bumpers and extended taillights mounted on long stalks, distinguishing it from the earlier 4AB.
Initially, production of the 4AD focused on export markets, whereas the smaller 4AB continued to be sold in the UK. By 1953, the 1.5-litre 4AD was also introduced to domestic buyers.
A road test conducted by The Motor magazine in 1951 recorded a maximum speed of 73 mph, acceleration from 0 to 60 mph in 23.6 seconds, and fuel efficiency of 25.8 mpg (imperial). Pricing details were not released due to its export-only status at that time.
Singer SMX Roadster 1953
This experimental variant featured a body constructed from glass fibre and was presented at the Earls Court Motor Show in October 1953. Production was extremely limited, with approximately ten units built.
