The 4/4 was actually the first four-wheeled car built by Morgan, and is named for its four wheels and four-cylinder engine. What with the 4/4 having entered production in 1936, the four-cylinder engine in question was producing a meager 34 horsepower. For 1936, that was really about all you could expect, but the unfortunate thing was that the next engine, which lasted from 1955 to 1960, was a side-valve Ford
design which produced 36 horsepower. That was pretty thoroughly obsolete by this point, although Morgan did manage to get away with it since the car was so very, very small and light.