Over the past eight decades the 20/25HP Rolls-Royce has earned an enviable reputation of being among the most dependable, satisfying and highest-quality pre-war models of all.

Produced from 1929 to 1935, it represented the Marque’s determined effort to move away from massive formal cars, routinely chauffeur-driven, to the newly-fashionable owner-driver market for the wealthy private owner-driver.

Of course it embodied Crewe’s routine programme of continuous mechanical development and improvement throughout its run, but the fundamentals of its superbly-crafted three and a half litre straight six driving through a four speed gearbox of amazing refinement remained the same.

By the late 1920s the trend for ever-heavier coachwork on the Rolls-Royce 20 HP had inevitably had a detrimental effect on performance.

Rolls-Royce’s solution was to increase the comparatively small six cylinder engine’s capacity from just over three litres to 3,699cc which, together with a stronger crankshaft allo...