Whilst it used a brand new 4-cylinder 2199 cc, overhead-valve engine - the first to be used in an Austin car, it in fact used the pre-war body from the Austin 12, which continued to be produced, alongside the other pre-war saloons the 8 hp and the 10 hp. The 'hp' (short for horsepower) was not a true reflection of the power of the vehicle, instead it was the result of a calculation to determine the excise duty (road tax) payable for the vehicle. The engine in fact produced 67 bhp (50 kW) at 3800 rpm. The car shared a number of features in common with the famed London Taxi, one of which was the built-in hydraulic jacking system operated from a pump located under the bonnet.
The 16 hp had a healthy turn of speed for its day with a maximum quoted speed of 75 mph (121 km/h). In the bitterly cold winter of 1947 Alan Hess and a team of drivers with 3 Austin 16 hp vehicles undertook a publicity run on behalf of the Austin Motor Company to visit seven Northern European Capitals in seven days. Despite extraordinary travel difficulties caused by heavy snow, the vehicles completed the adventure successfully, and the story is related in Alan Hess's book, Gullible's Travels.