During the 1930’s Rolls-Royce had been experimenting with a centrifugal supercharger. The aim was to boost the power of the Bentley sixes with the unit running at six times the engine speed. Rolls Royce was commissioned in 1946 to design a supercharger for the P15 BRM under the direction of Geoffrey Wilde. The result was an innovative two-stage centrifugal supercharger derived from a Merlin engine. With a 6in diameter in