Mallock's father, Arthur, was described by his biographer Paul Lawrence as the man most responsible for making motor racing accessible to the ordinary person, through the affordable front-engined Mallock U2 racing cars that Arthur began producing commercially in 1958. Growing up in that environment shaped Ray Mallock's ambitions from an early age. Arthur raced at Brands Hatch during Ray's childhood; watching his father start from the back row and come through to win left a lasting impression. For his fifteenth birthday Arthur gave him a 1936 Austin Seven Ruby, which he immediately set about lightening by removing the body before rolling it in a field — an incident that did not discourage him.
Without academic qualifications from school, Mallock obtained an apprenticeship with Aston Martin at Newport Pagnell, where he learned to use a lathe, weld, and do electrical work while on the chassis line building DB6s. He also worked in the company's Sales and Distribution department, taking cars to television productions.
Mallock made his competitive debut in 1969 at Silverstone, starting from the grid in a Mk9 Mallock Formula Ford that he had largely built himself, finishing ninth. He went on to win the Clubmans Championship outright in 1970. He then set up his own business, Rayce Developments, which supplied wheels and exhausts to Mallock Racing and prepared customer cars. The 1971 Clubmans season produced 22 wins and nine lap records, after which he made his Formula Three debut in the Mallock Mk11B and earned a Grovewood Award.
He moved into Formula Atlantic in 1973, starting with an ex-James Hunt March sponsored by The Chequered Flag, and finished runner-up in the championship in his first season. Over the following years he continued in Atlantic, touring Europe with a three-man crew. He also competed in Formula Two in a Chevron B40, and in British Formula One in an Ensign and a March, between 1978 and 1980. He won the British Formula Atlantic Championship in 1979 in a Ralt RT1. He won the championship again in 1981, by which time Bernie Ecclestone had offered an F1 test drive at Brabham if he took the title, but the test never materialised. Mallock concluded he was too tall for Formula One and, at 30, too old.
Mallock made his Le Mans debut in 1979, finishing twentieth and third in the Sports 2.0 class in a De Cadenet-Lola shared with Martin Raymond and Simon Phillips.
From 1982 he became involved in the Aston Martin Nimrod Group C programme. He persuaded Victor Gauntlett and Viscount Downe to fund a quarter-scale wind tunnel model at MIRA to address the car's aerodynamic deficiencies — an area in which he educated himself with help from a senior British Aerospace aerodynamicist who had worked on Concorde. At Le Mans in 1982 the two works Nimrods failed to finish while the Viscount Downe privateer car driven by Mallock, Simon Phillips, and Mike Salmon experienced engine problems and lost a hard-fought third position before crossing the line seventh. The programme ended in 1984 following a tragic accident at Le Mans that involved both works cars and killed a marshal.
From 1985 to 1987 Mallock designed, developed, and operated the Ecurie Ecosse Group C2 cars. Using Austin Rover engines, the programme won the C2 class of the World Sportscar Championship in 1986. Across the three seasons Mallock won eight rounds of the World Sportscar Championship in cars of his own design and construction.
He was also responsible, together with Canadian chief designer Max Boxstrom, for designing and developing the Aston Martin AMR-1 Group C1 car. He made his final racing start in the AMR-1 at Le Mans in 1989, retiring from race driving that year after losing confidence in himself as a development driver and gaining sufficient confidence in the abilities of David Leslie to take a step back.
Mallock had established Ray Mallock Atlantic Racing — the forerunner of RML — in the late 1970s to run his own cars and take on engineering development work. Following the AMR-1 programme, which had been subsumed by Victor Gauntlett's Proteus Technologies, Mallock reconstituted RML from scratch. After a one-race appearance with Nissan at the 1990 Le Mans, he identified the British Touring Car Championship as the logical next direction for the business. Vauxhall Dealer Sport lent two 1991 Cavaliers for the 1992 season; RML produced its own cars in 1993, and by the end of that year had impressed Vauxhall enough to be awarded the works contract. John Cleland won the BTCC championship in the RML-run Cavalier in 1995. RML subsequently ran Nissan and later operated the Chevrolet works team in the World Touring Car Championship up to 2014.
Since 2016 the company has been led by Mallock's son Michael, himself a racing driver, and has diversified with reduced emphasis on motorsport competition. Mallock retired from active involvement to pursue historic racing in older Mallock machinery, including cars that had originally belonged to his father.