Work by Rover began in earnest following the of the Range Rover in March 1970, and the new car rapidly took shape. As with the P6, David Bache did not want a contemporary design; when it came to his new car, he wanted something that was ahead of the game, and with the P10, he decided very early in the development phase that he wanted a hatchback configuration, and that he wanted the Rover to look exclusive.

Whilst David Bache worked on Rover's model, initially to be called the P10, Triumph's design team worked on a Michelotti-styled scheme – codenamed Puma – in consultation with William Towns. Basically, this internal competition was brought to a close when Leyland's management, headed by Donald Stokes, brought both teams together in February 1971, with a view to the better of the two cars becoming the new large Rover/Triumph saloon. In this “head to head” competition, Rover's car was adjudged to be superior by Donald Stokes and John Barber, so development resources were exclusively directed to David Bache's design.

This result proved to be a happy coincidence, as there was already a feeling that the new large car should be marketed only as a Rover. After all, Triumph's range at this time consisted of smaller cars (later to be umbrella'd under the Dolomite name) and the slightly cheaper of the two ranges in the 2-litre class (Triumph 2000/2500). Thus, it was decided that a smaller car could be developed in the future to replace the Toledo/Dolomite, and badged as a Triumph. It was at this point in the development of the car that the P10 was renamed RT1 (denoting Rover-Triumph), to signify that this was a car that integrated both Triumph and Rover engineering.

Picture Information: SD1 Clay model poses alongside some rather exotic Italian machinery for comparative purposes. (Picture supplied by Ian Nicholls)