The Bristol 407 is a sports tourer car produced by British manufacturer Bristol Cars between 1961 and 1963. It was the first Bristol model to be made by the company after separating from the Bristol Aeroplane Company, which had built all previous Bristol models. Outwardly it resembled the 406, on which it was based, and which had been produced between 1958 and 1961.
Background
Unlike its predecessors, the Bristol 406 suffered from a lack of power: Bristol's BMW-derived 105 bhp inline six-cylinder engine (type 110) no longer enabled the 1.5-ton car to achieve the sporty driving performance that distinguished earlier Bristol models. A further increase in performance of the engine, the concept of which dated back to before the Second World War, could no longer be achieved.
Bristol was therefore looking for a new engine in the second half of the 1950s. First, the company started to develop its own, new engine, designated type 160. The key requirement was a six-cylinder configuration and a displacement of 3.0 to 3.5 litres, similar to that of contemporary Alvis engines. However, the performance of the first prototypes was not convincing; in any case, the parent company was of the opinion that the financial expense of the new construction was not commensurate with its benefits. In 1959, Bristol tested another in-line Armstrong Siddeley six-cylinder engine. The 4.0 litre engine was standard in the Armstrong Siddeley Star Sapphire and produced 165 bhp. Bristol equipped a 406 with this engine and carried out some test runs at the factory. However, there was no takeup into series production. The prototype went on sale and was in regular use until 1975.