The story starts in 1953 when Jem Marsh bought his first car, a part built Austin Seven Special from "somewhere near Brooklands" and rebuilt it with the help of his stepfather Anton De La Rue. At the time it had an Austin Seven two-bearing crank type engine and rear axle. Following a collision between the Special and a lorry that put Jem in hospital with a broken leg and internal injuries, he decided to rebuild the car again. In the process the old front suspension was altered from a double wishbone system that used elastic bungees looped around aluminium pulleys (like the Kieft 500 rear engined car) to a wishbone system that used a transverse leaf spring. It was far more reliable according to Jem! The car also used A7 side rails to conform to the then 750 Formula regulations but it was barely legal!

In 1954 Jem entered his first race, the 750MC three-hour relay race at Silverstone. This was as part of a four-car team, however after half an hour three cars from the team had broken down leaving Jem to drive the remaining two and a half hours alone. In doing this he set a record for the greatest number of laps driven by a single 750 car in the three-hour relay race, a record that still stands.