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1962 Lotus Seven

The Lotus Seven was introduced in 1957 and was the company's first serious production car. The 7 would become an unqualified commercial success for Lotus, one which exemplified company founder Colin Chapman's 'added lightness' performance maxim. The name 'Seven' was left over from a model that was abandoned by Lotus, which would have been a Riley-engined single-seater that Lotus intended to enter into Formula Two competition in 1952 or 1953. Instead, the car was built around Chapman's chassis as a sports car by its backers and called the Clairmonte Special.

During its production lifespan a great deal of development work was applied to the 7 along four distinct series. The original S1 had a tubular spaceframe chassis, wishbone and coil spring independent front suspension, a live rear axle, and simple open bodywork. The S1 would establish the basic formula and components of the 7, all of which would continue through all four iterations of the car. It was designed to accommodate a variety of engines, with the basic powerplant being the 40 horsepower, 1172cc side-valve four-cylinder Ford engine, with BMC A-Series and Ford 105E overhead valve units available later. When the 7 received the 1,098cc Coventry Climax engine, the cars were known as the 'Super 7.'

In 1960, Lotus introduced the S2 which brought with it a simplified and revised spaceframe. The Super Seven was now available with a Cosworth-tuned Ford 1,340cc engine intended for SCCA racing in the United States, later in 1.5- or 1.6-liter displacements. The main update of the following S3 version, introduced in 1968, was a strengthen chassis with stressed front bulkhead. Caterham production would take over during the S3 run. In 1970, Lotus radically changed the shape of the car to create the slightly more conventional sized Series 4, with a squarer fiberglass shell replacing most of the aluminum bodywork. It also came with some 'luxuries' as standard, such as an internal heater matrix.

by Dan Vaughan

Roadster (S2)

The Seven was Lotus' first serious production car when it was introduced in 1957. It was lacking in just about every comfort and convenience feature. In fact, it was initially available only in kit form. It was soon available in fully finished form. The light weight of the car made it a swift performer despite standard engines being in the forty horsepower range.

The Series 2 was introduced in 1960. It featured full fenders as opposed to the original model's cycle fenders. Export models included up-market equipment such as a windshield wiper, spare tire, hubcaps, side curtains and a top. By the time Series Two production ended in 1968, a total of 1,350 had been made.

The Lotus Seven was the successor to the Lotus Mark 6 and was in production from 1957 through 1972. It was introduced to the public at the Earls Court Motor Show in London in October 1957. Colin Chapman, the founder of Lotus, had designed six other Lotus's; this vehicle being his seventh. Part of the vehicle's success was its lightweight construction and powerful engines resulting in great performance, handling, and response times. It went from zero to sixty in around 5 seconds and had a top speed of about 100 miles per hour. Chapman used to refer to the vehicle as a 'four wheeled motorbike'.

There were few amenities, the seats were not adjustable and there were no doors. The car sits very low to the ground. While sitting in traffic, the driver measures about as high as most vehicle's wheel-wells. The front suspension was an independent A-arm while the rear was a live axle located by twin parallel trailing arms and a diagonal link. The body was constructed of a steel tube frame with aluminum bodywork and fiberglass fenders. Cast-iron drum brakes were used to stop the vehicle. Initially, a worm-and-nut steering was used but was quickly replaced with rack-and-pinion.

The cost of owning the first sevens was £587 (around $1640). They featured a Ford engine producing 40 horsepower and a Ford gearbox. The first few years of its development saw improvements to the suspension, transmission, and engine capacity.

Series IF, introduced in 1957, had a length of 129 inches and a width of 53 inches. In 1958, the IC Series was introduced with a length of 132 inches and a width of 58.30 inches. The engine was a Coventry Climax FWA 1098 light-alloy, four-cylinder powerplant that produced 75 horsepower. The transmission was the BMC Austin A30 4-speed manual with optional close-ratio gears. The 1A AWD America Series was introduced at the close of 1959. 37 horsepower was ascertained from the BMC A-Series 948 cc. four-cylinder engine. The United States versions were dubbed the Seven America and were equipped with Austin-Healey Sprite engines outputting 43 horsepower. In 1960 the Series 2A and 2F were introduced. These 2A's featured a BMC A-Series engine and a BMC Sprite 4-speed manual gearbox. The American versions were given a 948 cc. or 1098 cc. engine. The 2F Series featured a 100E Ford engine and Ford 3-speed gearbox. This was later exchanged in favor of the Ford 105E 997 cc engine and 4-speed Ford Anglia gearbox.

Caterham obtained the rights to build the Seven after Lotus had ceased production. They continue to produce the vehicle to this day but added the 'Super' to the front of the name. Not much has changed since the vehicle's inception except that it has grown in size and there have been suspension, frame, and other mechanical enhancements. Disc brakes were placed on all four wheels. The suspension was modified to use a double wishbone in the front and a De Dion in the rear. The transmission has been modified to include a six-speed close-ratio gearbox. A catalytic converter can now be found attached to the underbelly of the vehicle.

In 1999, the Caterham R500 was introduced. With a zero-to-sixty time of 3.4 seconds and a top speed of 146 miles per hour, it is by far the quickest and fastest of the Sevens.

The Super Seven SV is the largest of all the Seven's. Its width was extended by four inches and the length was lengthened by three inches. It is powered by a Ford Zetec engine that is capable of producing 147 horsepower. The zero-to-sixty miles per hour is achieved in just 4.6 seconds.

The Seven has been so successful in racing that in 1976, it was banned because it was too fast. Caterham has since created its own racing league giving the drivers an opportunity to prove their skills on the race track.

During its forty-year lifespan, multiple engines and various mechanical configurations have been used. The key to its success is the fun-factor. It is a responsive and sporty vehicle. It has stayed street legal because of its kit-car status, a loop-hole that has continued the allure and enjoyment of this vehicle even to this day.

by Dan Vaughan