McLaren M7B

Bruce McLaren Motor Racing was founded in 1963, initially with Bruce McLaren competing as a factory driver for the Cooper team. From 1966, the team began designing and building their own Formula One cars. The first two seasons proved challenging, yielding only six points and a best finish of fourth. A major constraint was the availability of a competitive engine. The 1966 M2B utilized underpowered Ford and Serenissima V8 engines, while the 1967 M5A was delayed until mid-season, arriving with a British Racing Motors V12. The introduction of the Cosworth DFV engine in 1967, initially exclusive to Lotus, offered a potential solution. McLaren secured five DFV engines in 1968 at a cost of 7,500 pounds sterling each.

The design team included Robin Herd, recruited in 1965 from the National Gas Turbine Establishment (NGTE) where he had worked on the Concorde project, and his assistant, Gordon Coppuck, also an ex-NGTE employee. Herd initiated the M7A’s design in late 1967 but departed to join Cosworth before its completion, leaving Coppuck and Bruce McLaren to finalize the project.

The M7A was a mid-engined, open-wheeled single-seater. Its chassis was a bathtub-type monocoque, initially constructed from 22-gauge aluminium alloy panels riveted and glued to three steel bulkheads. Magnesium alloy was used for non-stressed panels like the dash and battery cover. The engine served as a stressed member, bolted directly to the rear bulkhead, with the gearbox attached behind it. Suspension consisted of lateral links, radius arms, and wishbones, front and rear, utilizing coilover springs and initially Koni dampers, later replaced by Armstrong units.

The car’s bodywork largely comprised the monocoque, supplemented by glass-reinforced plastic (GRP) panels for the nose and cockpit. The wheelbase of the initial prototype (M7A/1) was 7ft 9.6", with subsequent versions (M7A/2 and M7A/3) extended to 96.5". Track widths were 58 inches (1,500 mm) at the front and 57 inches (1,400 mm) at the rear, with a total weight of 1,140 pounds (520 kg). McLaren used their own magnesium alloy wheels, 15-inch at the rear and 15- or 13-inch at the front. Fuel capacity was 40 imperial gallons (180 L), stored in tanks along the chassis sides.

The M7B was a one-off modification of M7A/3, focusing on fuel tank placement. It featured low, central fuel bags housed within aluminium pontoons riveted to either side of the cockpit. This design aimed to improve handling by altering the car’s weight distribution, inspired by the superior handling characteristics observed in sports racing cars.

The 1968 season saw Bruce McLaren partnered with Denny Hulme, the reigning World Champion. The M7A debuted at the non-championship Race of Champions, where McLaren won. Hulme secured victory at the BRDC International Trophy. In the World Championship, Hulme finished second in Spain, while McLaren retired. The M7A achieved its breakthrough win at the Belgian Grand Prix, marking McLaren’s first Formula One victory. Despite subsequent challenges with Goodyear tyre performance, Hulme retired at the Dutch Grand Prix with ignition failure, but secured a win at the Italian Grand Prix at Monza, and McLaren and Hulme finished first and second in Canada. Hulme ultimately finished second in the Drivers’ Championship.

In 1969, with the development of the four-wheel-drive M9A underway, McLaren continued to race the M7A and M7B. Hulme achieved a podium finish with the M7A in South Africa, and Bruce McLaren used the M7B. Hulme won the Mexican Grand Prix. The M7B was later driven by Vic Elford of the Colin Crabbe Antique Automobiles team, achieving a tenth-place finish at the Dutch Grand Prix before a crash at the Nürburgring destroyed the car.

The M7 had limited works outings in 1970, with Dan Gurney using an M7A at the British Grand Prix. Privateer John Surtees purchased the M7C as an interim solution and raced it at four Grands Prix. By 1971, Jo Bonnier was the sole entrant, racing the M7C at five races.

The M7C featured a fully enclosed monocoque, offering increased torsional rigidity, derived from the M10A Formula 5000 chassis. Only one M7C was produced.

The M7D was commissioned by Alfa Romeo’s Autodelta and powered by a 3.0-litre V8 engine from their T33 sports car, producing between 410 and 430 bhp (306–321 kW). A new mounting point was required for the alternator, differing from the DFV arrangement. Only one M7D was built.

The M7A and M7B established McLaren as a competitive force in Formula One, paving the way for future success with the Cosworth DFV engine. A detailed replica of the McLaren M7B was created for the PC racing simulation Grand Prix Legends in 2005.