Large, powerful, four-cylinder cars with capacities as large as 7.7-litres had been a feature of Oldsmobile's range in the late 1900s, but it was not until 1914 that the company downsized the concept to create the first four-cylinder 'baby' Olds, the Model 42.

The Model 42 was joined the following season by the slightly larger Model 43, with 'valve-in-head' engine, only for the four-cylinder Olds to disappear from the range almost immediately.

Revived in 1921 as the Model 43-A, the four-cylinder model would be Oldsmobile's top seller for the next few years and an immense success for the company until rationalisation saw the range confined to six-cylinder designs from 1924 onwards.

The Oldsmobile Sixes had commenced in 1923 with the first of the Model 30 series, which for the next few years would be powered by a 169ci (2,770cc) engine producing 42bhp.

For 1927, the last year of the Model 30, the engine was enlarged to 185ci (3.0-litres) and four-wheel brakes adopted on these Series ...