Rover SD1 is both the code name and eventual production name given to a series of large executive cars made by British Leyland or BL through its Specialist, Rover Triumph and Austin Rover divisions from 1976 until 1986.
In "SD1", the "SD" refers to "Specialist Division" and "1" is the first car to come from the in-house design team. The range is sometimes wrongly referred to as "SDi" ("i" is commonly used in car nomenclature to identify fuel injection).
In 1971,Rover, at that time a part of the British Leyland (BL) group, began developing a new car to replace the P6 and the Triumph 2000/2500. The designers of both Triumph and Rover submitted plans for the new car, of which the latter was chosen. David Bache was to head the design team, inspired by exotic machinery such as the Ferrari Daytona and the late 1960s design study by Pininfarina for the BMC 1800, which also guided the design of the Citroën CX. Spen King was responsible for the engineering. The two had previously collaborated on the Range Rover. The project was first code-named RT1 (for Rover Triumph Number 1) but then soon changed to SD1 (for Specialist Division Number 1) as Rover and Triumph were "put" in the new "Specialist Division" of BL.
The new car was designed with simplicity of manufacture in mind in contrast to the P6, the design of which was rather complicated in areas such as the De Dion-type rear suspension. The SD1 used a well-known live rear axle instead. This different approach was chosen because surveys showed that although the automotive press was impressed by sophisticated and revolutionary designs the general buying public was not, unless the results were good. However, with the live rear axle came another retrograde step – the car was fitted with drum brakes at the rear.
Rover's plans to use its then fairly new 2.2 L four-cylinder engine were soon abandoned because BL management ruled that substantially redesigned versions of Triumph's six-cylinder engine were to power the car instead. Rover's Rover V8 engine was fitted in the engine bay. The three-speed automatic gearbox was the BorgWarner 65 model.
The dashboard of the SD1 features an air vent, unusually, directly facing the passenger. The display binnacle sits on top of the dashboard in front of the driver to aid production in left-hand drive markets. The air vent doubles as a passage for the steering-wheel column, and the display binnacle can be easily fitted on top of the dashboard on either the left or right-hand side of the car.
An estate body had been envisaged, but it did not get beyond the prototype stage. Two similarly specified estates have survived, and are exhibited at the Heritage Motor Centre and the Haynes International Motor Museum respectively. One was used by BL chairman Sir Michael Edwardes as personal transport in the late 1970s.
The SD1 was intended to be produced in a state-of-the-art extension to Rover's historic Solihull factory alongside the TR7. It was largely funded by the British government, who had bailed BL out from bankruptcy in 1975. Unfortunately this did nothing to improve the patchy build quality that then plagued all of British Leyland. That, along with quick-wearing interior materials and poor detailing ensured that initial enthusiasm soon turned to disappointment.
Initial model and first additions to range
In 1980 Rover obtained US type approval for the SD1 and re-entered the American market after a ten-year absence. The car was only made available as a single variant, using a modified version of the V8 engine and badged simply as "Rover 3500". The equipment and trim levels were similar to that of the UK market's then top-of-the-range V8-S model. The main differences were a smaller steering wheel, the sunroof (moonroof) being a cost option and rear passenger head restraints were not available at all. Small Union Jack decals were fixed to the lower section of each front wing, just ahead of the doors, to promote the car's British origins. The five-speed manual gearbox was supplied as standard, with the three-speed automatic version being a cost option.
US safety legislation (that first applied to the Citroën DS) demanded that the headlamp arrangement excluded the front glass panels. Also larger, heavier bumpers were required.
American emissions regulations necessitated other differences including replacement of the carburattors with Lucas' L-Jetronic fuel injection system and the fitting of dual catalytic converters, a modified exhaust manifold and de-smogging equipment. The engine's compression ratio was modified to 8.13:1. Publicity material claimed it was capable of reaching 148 hp (SAE) but the car as sold actually peaked at 133 hp (at 5,000 rpm).
Despite the necessary modifications, Rover chose not to set up an assembly plant in the US but built and shipped the cars from the Solihull factory.
The SD1 gained positive reviews in the American press and was competitively priced against rivals such as the BMW 5-series. Nevertheless the car achieved just 480 sales between its launch in June 1980 and the end of that year. The whole of 1981 attracted 774 sales (although most of these cars had actually been built and stockpiled the previous year).
Rover ceased the supply of American market SD1s at the end of 1981, although unsold cars remained available from dealers well into the following year.
Reasons for the commercial failure of the SD1 in the US are open to speculation. The weak value of the American dollar against European currencies at the time rendered imports relatively expensive in comparison to home-built product. A significant rise in oil prices during 1979 led to many motorists opting for more fuel-efficient cars. Public awareness of the SD1 may have been low as the dealership network across America was small, while Rover's expenditure on the aforementioned modifications, testing and approval for the US market left limited budget for publicity and advertising. (To save money the official press launch was combined with that of the Triumph TR8 .)