M03

The Typ 300 was the largest of the three cars Porsche showed in Berlin in October 1926 — comfortable, ponderous and slow to sell. Deliveries began in January 1927, and within months the model was being reworked. The original 2,968 cc six gave way to the M03, bored from 74 to 76 mm, still rated at 55 PS but reaching it at 3,200 rpm rather than 3,500, and paired with taller final drive to lift the top speed past 100 km/h.

The change was almost invisible to buyers, who responded accordingly: 834 cars with the first engine, then 2,485 with the M03. Side valves, one camshaft in the block, a single Zenith flat-stream carburetor and mechanical brakes on all four wheels were respectable rather than advanced — Horch had had an eight-cylinder car since 1926, and Stuttgart would have nothing to set against it until 1928. The Typ 300 was revised again as the W 04, the second of three attempts to make it sell.