Thompson fitted his racing in with his work schedule. Twice winning his class at Le Mans and victories at Spa, Goodwood and other circuits, though he drove for fun, Thompson drove like no amateur. He only competed in one Grand Prix, the British in 1952, beating Farina in a straight fight for fifth place and two points.
Born in Ditton Hill, near Surbiton in Surrey, Thompson didn't start racing until after the II World War. Following demobilisation from the Army in 1946, Eric started working as a Marine Insurance Broker at Lloyds. His first invovement in motor sport was driving a TB MG and a Ford V8 in Trials and Rallies. He enjoyed some success and in 1948 he made his circuit racing debut in the Paris 12 Hours at Montlhery. Robin Richards (an Alpine Cup Winner) invited Eric to co-drive his 1100cc HRG as part of the victorious BRDC Team versus the French AGACI, coming 4th in class and 17th overall at an average speed of 58.66mph.
Filled with enthusiasm, he commisioned Monaco Motors to build him a car based on a damaged 1.5 litre HRG chasis he had bought from Charles Follet.
Then for his second race he went to Le Mans in June to drive another HRG entered by Ecurie Lapin Blanc. With Jack Fairman as co-driver, Thompson won his class, finishing 8th overall. They then won their class at the Spa 24 Hours in July. Racing his own lightweight HRG in England, he entered the Goodwood Handicaps in August and took two wins, folllowed by a 1 hour Production Car Race at Silverstone later that month. Once again Thompson won his class. A dissapointing 6th in class at the Prescott Hillclimb rounded out an amazing year.
In his first six races he took five wins which included Le Mans and the Spa 24 hour races! Thompson might have been an amateur who raced for fun, but he drove as well as any professional.
In 1950 he became a member of the Aston Martin sports car team, where he stayed until 1954. His first race for Aston was in a one hour production race at Silverstone, finishing 4th in his class. At Le Mans he shared an Aston Martin DB2 with American John Gordon, but they retired with engine problems after only 9 laps. Thompson continued to campaign his HRG and took a class win (and 2nd overall) in the 1 hour Production Car Race at Blandford, 3rd in a Goodwood Handicap and another class win (and 3rd overall) in the Cambridge University Sprint at Bedwell Hey. 1950 saw Eric try single-seaters entering a 500cc F3 Cooper Vincent at Castle Combe.
He did eight races in 1951. He raced the Cooper, finishing 5th in the Lavant Cup at Goodwood, and drove a Bugatti T51 and Rob Walker's ERA/Delage and Delahaye in Libre races In sports cars he drove Walker's Aston Martin DB2 to 8th overall and 3rd in class at the Tourist Trophy. At Le Mans he drove a works DB2 with Lance Macklin, crossing the line 3rd overall, winning the 3 litre class, his second Le Mans win.
In 1952 at Le Mans, he again drove a works Aston Martin, this time a DB3, with Reg Parnell, but retired from transmission problems. Thompson and Parnell then entered the Goodwood 9 Hours. Thompson had a lucky escape when, after pitting to change drivers, he was suprised when Parnell pulled him out and away from the car. Seconds later the car went up in a ball of flame. The car had been overfilled and the fuel ignited on a red hot seized rear brake calliper.
Amongst other races, he won two handicap events, at Goodwood and Snetterton in one of Rob Walker's DB2s, and raced Walker's ERA/Delage and Delahaye in single-seater races. Eric also raced his own ERA. He also raced a Connaught A-Type (A6). He took pole for the Madgwick Cup at Goodwood, but he crashed in the race. He then came 6th at Charterhall. In July he raced the Connaught in his only Grand Prix appearance, the British Grand Prix.
Though this was a works car with a Lea Francis engine it was not the most competetive machine and Farina, Ascari and Taruffi in their Ferraris were miles ahead of the pack. Thompson put his car in 9th spot on the grid, ahead of the likes of Prince B Bira, Duncan Hamilton, Peter Collins, Rudi Fischer, Ken McAlpine, Stirling Moss, Roy Salvadori, Peter Whitehead, Maurice Trintignant, Baron Emmanuel de Graffenried and Harry Schell. Thompson got away cleanly and he moved him up a spot when Manzon retired. Eric drove well and crossed the line in 5th place beating Farina by 13 seconds in a straight fight. The shame of it was that this was his only GP as he undoubtedly had the ability to score more points.
In 1953 at Le Mans he drove an Aston Martin DB3S with Poore, retiring after 182 laps with ignition failure. With the Goodwood 9 Hour race, Parnell and Thompson returned to the scene of their drama the previous year. For the first 169 laps everything went to plan but a puncture then set them back. 53 laps later they made the last driver change with Eric taking over from Parnell. The clutch would not disengage, but Eric managed to rejoined the race. It was dark and with 2 hours, 15 minutes to go, he was lying 4th, 4 laps behind the leading Jaguar. In a sterling drive Thompson pushed on and as midnight arrived he crossed the line to take the chequered flag. Eric and Parnell then went on to take 2nd in the Tourist Trophy behind the other works car. He did 8 other races that year including two F2 wins at Snetterton in April and September, and a 2nd in a Libre race driving a Connaught (A3).
By 1954, the pressure of work was taking its toll and, apart from 6 laps at Goodwood with an Aston Martin DB2, driving at Le Mans in the works V12 Lagonda DP115 with Poore was his only outing, spinning out at the Esses after only 25 laps.
1955 saw him in a works 1.5ltr Connaught AL/SR Lea Francis with Ken McAlpine at Le Mans and the Goodwood 9 Hour Race, retiring in both. A CUAC Sprint the following Spring in a 500cc Jason was his last competitive event with a Class win. At the end of the year he announced his retirement.