In March 1969, Rover embarked on a new project to replace the P6. The Rover P10 would last until 1971, but its influence would be far greater than its ‘cancelled’ status would imply.
Read full story of this fascinating might-have-been as pieced together by Keith Adams, Chris York and Ian Nicholls.
Project P10: the final Rover
The seeds of the Rover P10 were sown in March 1969 when in an initial concept briefing, the bones of this new car were created. It would be the car to replace the Rover P6 – a job that had originally been down to the Rover P8. But since Rover’s takeover by Leyland in 1966 and subsequent now evolving into an altogether larger car, a direct replacement was needed. By March 1970, it was beginning to take shape as a four-door saloon and five-door fastback, which in latter form is pictured above.
As you’d expect from David Bache, the initial design concept was nothing if not radical for the time for a car of this market sector. But as it was replacing the the P6, a car that was equally as progressive at launch in 1963, this was to be expected.
By June 1970, the Rover P10 package drawings were passed to the Styling Department with a view to dressing it up as a viable executive challenger for the 1970s. The Rover Board was told at that time that the P10 would expected to be launched in Autumn 1974. Power would come from the venerable all-aluminium Rover V8 engine for the top versions.
Rover decided to adapt what it already had and started work on a development of the 1978cc four-cylinder engine found in the P6 saloon. The engine was a twin-cam, four valve per cylinder engine of 2204cc (below). The extra capacity was achieved by increasing the bore. Five or six prototypes were built, including one with Bosch L-Jetronic fuel injection and a double overhead cam head (below) which produced 170bhp on the testbed. Routine enough now, but this would have been revolutionary for a volume car in 1973…
On 11 December 1970, the Triumph Board was informed that it would have to drop the 2000/2500 replacement programme, known as the Puma, in favour of the Rover P10. The British Leyland corporate executive car would be engineered by Rover, which in light of the P6’s sales supremacy over its Triumph rival, was an understandable decision. Even if it would effectively decapitate Triumph’s model range in the future.
On 11 February 1971, the BLMC Board met at Solihull to view scale models of the proposed replacements for the Rover P6 and Triumph 2000/2500. David Bache’s team produced six P10 scale clay models, five hatchbacks and a notchback, for consideration by the Board. However, Triumph was still in the running to style the corporate executive car and brought along a model of its Puma proposal. Both projects were brought together for assessment, but the Board opted for the Rover P10. Triumph’s Puma was thought to be too conventional in style.
It was at this point that the Rover P10 was rebranded the RT1 (for Rover-Triumph 1). As well as the overall design concept surviving reasonably intact to become the Rover SD1 we all know and love, the P10’s slant-four 2.2-litre twin cam was put to good use as the cylinder boring tools for that engine were used in the post-1974 facelifted Rover P6 2200.