So you might be scratching your head thinking 22hp?
An important thing to note is the “22hp” refers to an arbitrary number arrived at by mathematical equation and bears no relation to actual power output. The equation was invented by the Royal Automobile Club and effectively multiplies cylinder diameter by the amount of cylinders. This created an engineering culture favoring long-stroke, narrow bore engines and was probably the worst thing that ever happened to the British motor industry. It was all done purely for tax reasons.
It’s important to note that two British cars, of the same year, and the same RAC Horsepower rating, can be significantly different in both engine capacity and power output. For instance, a Riley Nine may deliver more BHP than an Austin Ten.
https://en.wikipedia.org/wiki/Tax_horsepower#Britain

This fascinating film has a Ford V8 22HP tell the story of it’s manufacture from the mining of iron ore right through to it being driven off the production line. Although very modern for its time, production at the vast Dagenham factory seems very hands-on by today’s standards.