Lotus 31

The Lotus 31 was a racing car produced by Lotus for the new 1-litre Formula 3 introduced in 1964, replacing the expensive Formula Junior. The chassis was a multi-tubular spaceframe, of similar design to the 1962 Lotus 22 Formula Junior. A 997 cc Ford Cosworth 109E with Single Choke Weber or SU carburettors produced Auto bhp|97|0 at 8000 rpm. The 31 had little success against the more advanced monocoque cars that dominated in 1964. Records show only 12 were built in 1964/65.

In 1966 19 cars were built with the Chassis 22/F3. The relative simplicity and low price of the car made it an ideal training car. Motor Racing Stables at Brands Hatch ran 4 cars to graduate students from Lotus Cortinas. Jim Russell ran the cars at Snetterton, later being recognised as a club under the RAC. JRRDS ran 5 31's at Brands Hatch BARC Trophy Races in July 1967.