It was originally introduced by Cooper for the 500cc race car. These race cars were running in the Formula 3 and in Formula Junior.
Cooper had a large clientele of drivers and their sponsors. Many of them had the desire to get into the highest class of motor sports. There they quickly found the answer and developed the T20. The T20 was based on the T15 and was much like it. The engine was mounted in a simple frame in front of the driver. The suspension and the wheels were taken from T15.
The engine was 2-litre unit from Bristol, a six-cylinder with a power output of 130 hp. Therefore, the car had to be light and competitive to beat, the then dominant, Ferraris. The car had indeed, as expected, been no chance against the vehicles from Italy.
For 1952 only very few teams and manufacturers committed to Formula 1 and the organisers of most Grand Prix decided to run their races for Formula 2 cars.
Originally only four T20's were completed for their first public outing, at the Goodwood Easter Meeting in 1952. It was there that Mike Hawthorn established his reputation by winning the Lavant cup, with second and third place also going to the new Cooper T20 Formula 2 cars.