In the early spring of 1951 the Mark IV version arrived with a larger, 2267 cc engine incorporating, as before, an aluminium cylinder head and with a 58 instead of 56 bhp output. However, at mid range speeds around 15 percent more power was generated. The Mark IV also used larger, 15-inch wheels. The steering was now more highly geared and was commended by commentators for its lightness when manoeuvering the car in a confined space despite 53% of the car's being carried by the front wheels.