Rolls Royce - Rolls Royce 20 HP
The Rolls Royce 20 HP was an all new model produced for the post first world war economic climate. Prior to this Rolls Royce only made one chassis model, the top of the range expensive 40/50 Ghost, and it was correctly reasoned that a smaller lighter and altogether more affordable model was needed to keep the company in business. The 20 HP model was produced between 1922 and 1929 with a 6 cylinder engine of 3,128cc with overhead valves. The power produced was 50 hp at 3,000 rpm. The 20 HP was arguably under powered, but since it was not built as a performance car, was a high quality machine perfect for the use to which it was intended. The Rolls Royce 20hp power plant later became the basis for the range of 6 cylinder engined Rolls Royces using the same basic engine, but with the bore enlarged from 76 mm to 82 mm, and by 1936 stretched further to 89mm.
The Rolls Royce 20 HP was fitted with the tyre size 32x 4 1/2 , fitted to 23" straight sided rims of the split rim type. Blockley produce this 32 x 4 1/2 tyre with the correct period tread pattern, as well as making a thicker correct inner tube to suit. Later models of the Rolls Royce 20HP were fitted with 21" wheels in which case Blockley can also supply the 525x21 tyre. Quite a few of the earlier 20HP were fitted 21" wheels by their owners much later due to unavailability (or the huge expense at the time) of the 32x4 1/2 tyres, before Blockley made this size! See full details of the two Rolls Royce 20 tyre size (32x4 1/2 and 525x21) at the links below.
