Power-to-weight ratio is a calculation commonly applied to engines and mobile power sources to enable the comparison of one unit or design to another. Power-to-weight ratio is a measurement of actual performance of any engine or power source. It is also used as a measurement of performance of a vehicle as a whole, with the engine's power output being divided by the weight of the vehicle, to give a metric that is independent of the vehicle's size. Power-to-weight is often quoted by manufacturers at the peak value, but the actual value may vary in use and variations will affect performance.
David Hepworth was a British racing driver, who won the British Hill Climb Championship twice, in 1969 and 1971. In the early-mid 1960s Hepworth drove an Austin-Healey 3000 fitted with a Chevrolet engine in both rallies and circuit racing, but by 1968 he was driving a Hepworth-Oldsmobile; in this he won a Formula Libre race at Croft late in that season.
The McLaren M4B was a Formula One racing car constructed by Trojan for Bruce McLaren Motor Racing and raced five times by New Zealander Bruce McLaren at the start of 1967.
Tony Southgate is an English engineer and former racing car designer. He designed many successful cars, including Jaguar's Le Mans-winning XJR-9, and cars for almost every type of circuit racing. He was responsible for the chassis design of Ford's RS200 Group B rally car. Southgate was employed as chief designer or technical director for many Formula One teams for over twenty years. These teams included BRM, Shadow and Arrows. Southgate retired after producing the Audi R8C, which was a major influence in the Bentley Speed 8, which won Le Mans in 2003. He continues to be a regular visitor to current and historic race meetings.
The McLaren M18 is an open-wheel Formula 5000 racing car designed and made by McLaren in 1971.
The Brabham BT36 was an open-wheel Formula 2 race car, designed by Ron Tauranac, and developed and built by British racing team and constructor, Brabham, for the 1971 European Formula Two Championship. Its best result that season was a 2nd-place finish in the championship for Argentine Carlos Reutemann, despite winning only one race, taking one pole position. His consistency and pace made this possible, scoring 6 podium finishes, and finishing the season with 40 points. The Brabham BT36 was constructed out of a complex tubular space frame, and was powered by the naturally-aspirated 1.6 L (98 cu in) Ford-FVA Cosworth four-cylinder engine, which produced 220 hp (160 kW), and drove the rear wheels through a 5-speed Hewland F.T.200 manual transmission.
The McLaren M8A was a race car developed by driver Bruce McLaren and his Bruce McLaren Motor Racing team for their entry in 1968 Can-Am season. The M8A and its successors dominated Can-Am racing for four consecutive Can-Am seasons, until the arrival of the Porsche 917.
The Chevrolet Corvette C8.R is a grand tourer racing car built by Pratt Miller and Chevrolet for competition in endurance racing. It serves as the replacement for the Corvette C7.R, using the C8 generation Chevrolet Corvette as a base. Corvette Racing fielded the C8.R in the IMSA SportsCar Championship GT Le Mans (GTLM) class starting with the 2020 season. The car was built to LM GTE specifications as per GTLM rules.
The Weslake V12 engine family is a series of four-stroke, 60-degree, naturally-aspirated, V-12 racing engine, designed, developed and produced by Weslake; between 1966 and 1992.
The Lola T160, and its evolution, the Lola T165, is a series of purpose-built Group 7 sports prototype race cars, designed and developed by British chassis manufacturer Lola Cars, specifically to compete in the Can-Am series in 1968. It was the successor to the competitive T70, sharing similar design knowledge and cues. Lola built the chassis, constructed out of fiberglass, and molded into an aluminum monocoque. This meant the car was light was lightweight, weighing only 670 kg (1,480 lb). The chassis was designed to accept a small-block engine, but most cars were powered by either the Chevrolet ZL1 or the Ford FE "big-block" motors, generating about 625–750 hp (466–559 kW); mated to a 4-speed or 5-speed Hewland L.G.500 or L.G.600 manual transmission. This made the cars very fast, with a notably excellent power-to-weight ratio. It was used in active competition until 1971, and was succeeded and used alongside the new T220 in 1970.
The BRM P154 is a purpose-built sports prototype race car, designed, developed and built by British Racing Motors to Group 7 racing specifications, specifically to compete in the Can-Am racing series, in 1970. It was BRM's first Can-Am car. It is powered by a naturally aspirated, Chevrolet big-block engine, developing 760 hp (570 kW), and 650 lb⋅ft (880 N⋅m) of torque.
The Brabham BT30 was an open-wheel Formula 2 racing car used in the 1969, 1970, and 1971 European Formula Two Championship.
The Chevron B24 was a Formula 5000 racing car developed by Chevron Cars in 1972.
The Brabham BT5, and its evolution, the Brabham BT8, are sports racing cars manufactured and developed by Brabham in 1963 (BT5) and 1964 (BT8), respectively. It won a total of 4 races, and achieved 10 podium finishes.
The British Racing Motors V8 was a four-stroke, naturally aspirated, 1.5 L (92 cu in), V-8 racing engine, designed, developed and built by British Racing Motors (BRM) to compete in Formula One racing (although an enlarged 2.0 L version was used for sports car racing. It was built between 1962 and 1967, and came in two version; the P56, and the P60.
The McLaren M1A, and its derivatives, the McLaren M1B and the McLaren M1C, are a series of mid-engined Group 7 sports prototype race cars built by McLaren, between 1963 and 1968. The M1A was the team's first self-designed and developed sports car. Later versions, such as the 'M1B' and 'M1C', competed and raced in the North American Can-Am series, starting in 1966 season. The car was raced in North America and Europe in 1963 and 1964 in various Group 7 and United States Road Racing Championship series events. 24 examples of the M1A and M1B were built, and 25 examples of the M1C were manufactured. They were powered by a few different motors, including Chevrolet small-block engine, an Oldsmobile V8 engine, a Chevrolet big-block engine, and even a Ford FE engine. It was constructed out of a tubular space frame chassis, and, combined with its light weight of 551 kg (1,215 lb) this gave it a great power-to-weight ratio. The 4.5 L (270 cu in) Oldsmobile V8 engine developed around 310 hp (230 kW), while the 350 cu in (5.7 L) Chevrolet small-block V8 engine was capable of developing over 550 hp (410 kW), and 538 lb⋅ft (729 N⋅m) of torque. This drove the rear wheels through a Hewland L.G.500 four-speed manual transmission.
The March 82G is a IMSA GTP/Group C sports prototype race car, designed, developed and built by British manufacturer and constructor March Engineering, for sports car racing, in 1982. It competed in motor racing between 1982 and 1986, but only scored 1 race win, 8 podium finishes, and 2 pole positions. It was powered by a naturally-aspirated 620 hp (460 kW) 5.7 L (350 cu in) Chevrolet V8 engine.
The Lola T220, and its evolution, the Lola T222, are Group 7 sports prototype race cars, designed, developed, and built by the British manufacturer and constructor Lola, to compete in the Can-Am championship from the 1971 season. It also took part in the European Interserie championship.
The Stealth B6 is a purpose-built grand tourer-style race car, designed, developed and built to GT1 rules and regulations, and used for sports car racing in 2000.
The BRM V12 engine is a V12 Formula One racing engine, designed, developed and built by British manufacturer and constructor BRM, between 1967 and 1977.
Howden Ganley 
Brian Redman