It is based on a mundane car.... a Rover 14hp. It's called the Eadon Special, or in other places a Rover Pilot Special. It was built by Major Alan Eadon in 1935/36 on a 1933 Rover 14hp base - he shortened the chassis, and underslung it to lower ride height, together with tuning the engine. He worked for Rover, which helped access to parts.