W.M. Iliffe was company secretary from the beginning and would continue for many years, also being secretary of the cycle company. Authorised capital of the new company was £40,000.

Some little while before the Sunbeam Motor Car Company was founded a drawing office had been built along with factory extensions, this was considered a bold move for at that time few firms had drawing offices which were considered an unnecessary luxury.

An advert from 1904.

Another 1904 advert.

By now Berliet cars were imported from France by a large London agent so Sunbeam needed to look elsewhere or design much more themselves. It was fortunate that Angus Shaw who had worked under Pullinger now proved to be a first class designer. He was appointed Chief Engineer and soon had his design for a 16/20 engine ready. Its four cylinders were cast separately and had dimensions of 95 x 120mm.  A sliding camshaft for the inlet valves controlled engine speed, and magneto ignition was used. The four speed gearbox of advanced design was fixed at three points to avoid any strains and chain sprocket bearings were part of the gearbox casting. The whole unit was made in two halves with a powerful countershaft brake contained inside the box. The 16/20 would prove to be a very successful car. Angus Shaw accompanied by Ernest Eastmead drove one of these cars from London to John O’Groats and back under official observation. The 1,756 miles was achieved without once stopping the engine. During this marathon journey 77 gallons of petrol were consumed which worked out at 22.8m.p.g., a very creditable performance.

It could be seen that there would be a good demand for this car, plans were afoot to produce ten per week, and land that had been acquired sometime previously was now used for further factory extensions in Upper Villiers Street.