Lotus Europa
The Lotus Europa name is used on two distinct mid-engine GT cars built by British automobile manufacturer Lotus Cars. The original Europa and its variants comprise the Lotus Types 46, 47, 54, 65 and 74, and were produced between 1966 and 1975.
The name was later revived in the Type 121 Europa S, a sports car based on the Lotus Elise produced from 2006 to 2010.
Europa (1966–1975)
By the mid-1960s, the mid-engine vehicle configuration was well-established as the optimal design for Grand Prix cars, however almost no road vehicles yet used this arrangement. Lotus planned the Europa to be a volume-produced, two-seater mid-engine sports coupe built to reasonable cost, quite an ambitious goal for the time. Like all Lotus vehicles of the era, the Europa was designed and built following Colin Chapman's oft-stated philosophy of automotive design: "Simplify, then add lightness". To this end, a number of ingenious design approaches were made by Lotus to allow it to economically overcome the many challenges presented by the novel mid-engine arrangement.Production of the original Lotus Europa ceased in 1975, with a total of 9,230 cars of all models having been built.
Design features
The Europa used a lightweight, folded and welded "minimalist" boxed-steel backbone chassis with a fibreglass moulded body, a combination that was first used by Lotus founder Colin Chapman in the Lotus Elan launched in 1962. Earliest versions of the Europa had the body fully bonded to the chassis for maximum structural stiffness, however this was soon changed to a bolted-on body to allow normal chassis and body repairs to be made. Unlike the Elan, the Europa had no front-mounted engine or gearbox to accommodate, and so the Europa's main chassis member ran straight forward to intersect a large box-section cross-beam running across the car between the front suspension points. At the rear, the chassis split into a "U" shape behind the cabin to accommodate the combined engine, transmission and final-drive components, and to support the rear suspension.Engine and transaxle
The sourcing of suitable engine, gearbox and final-drive components was considered critical to the success of delivering a low-cost mid-engine vehicle. Chapman was keen to diversify beyond the Ford components heavily used in earlier Lotus vehicles, and settled on using the engine and combined transmission/final-drive transaxle units recently released by Renault for its 16. The Renault engine was a light and modern design, while the matching Renault 16 transaxle seemed almost ideal for the Europa project. In the Renault, the transaxle sat ahead of the engine, driving the front wheels. By relocating the combined engine/transaxle unit to the rear of the car and rotating it 180 degrees in plan, Lotus could obtain a ready-made modern mid-engine configuration - albeit one with four reverse gears. By repositioning the differential crownwheel within the final drive assembly, the direction of rotation of the output shafts was reversed, thus correcting this shortcoming.The Renault 16's engine's design met Lotus's requirements. It used an aluminium block with cast-iron cylinder liners, which saved appreciable weight compared to the cast-iron blocks more common at the time. Its overhead-valve design had the camshaft located high-up in the block, resulting in a compact valve-train well suited for high-rpm operation. Most importantly, all the engine ancillaries were driven off a v-belt pulley fixed to the transaxle end of the camshaft instead of being driven by the engine's crankshaft. When fitted to the Europa, this pulley location put all the engine's ancillaries at its rear face giving easy access for maintenance, rather than them being located against the vehicle's bulkhead as-for most conventional engines.
For Lotus's use, the Renault engine was given a number of key improvements, including a higher compression ratio, larger inlet valves, revised valve timings, dual valve springs and a twin-barrel carburettor. These changes lifted the engine's power by 23% from at 5,000 rpm to at 6,000 rpm. For US export, a de-tuned version with a maximum output of at 6,000 rpm was fitted.
Later, Europa models were fitted with the same Ford-based Lotus TwinCam engine used in the Elan range since 1962. This was a sophisticated, twin-overhead-cam, 8-valve high-performance engine rated at in original specification. It was reported that Lotus initially delayed its introduction in the Europa until they were confident in the strength of the Renault transaxle. The twin-cam engine first appeared in the Europa engine bay in mid-1971 and early 1972. In North America, both the 1972 Twin Cam version and 1972-1974 Twin Cam "Special" versions were rated at in Federalized Form.
When Renault introduced its most powerful 16 TX model in 1973, it included a strengthened five-speed transmission. Lotus quickly offered this gearbox as an option in the Europa, along with the big valve twin-cam engine.
Suspension
The Europa's four-wheel independent suspension was also typical Chapman thinking. The front used lightweight pressed steel upper and lower wishbones with a clever coil-over spring-damper arrangement, all connected to the wheels using off-the-shelf front uprights, ball joints and trunnions.The steering gear was solid-mounted rack and pinion using components from the Triumph Herald.
The rear suspension was a heavily modified version of the Chapman strut, originally developed for Chapman's earlier Formula racing car designs and used in the Elan. In the Europa, the vertical "strut" element pivots on the wheel hub at its lower end and doesn't control wheel camber angle as-in earlier Lotus designs. Wheel location and alignment is controlled instead by interaction between a fixed-length, articulated driveshaft top link, a simple tubular lower link, and a large box-section radius arm running diagonally forward to the chassis. These radius arms played a critical role in giving the precise tracking and handling desired, as the Chapman Strut's use of the driveshaft to resist lateral forces was compromised by the rubber engine and transaxle mounts needed to isolate vibrations from the car body. A careful compromise between the radius arm mount's stiffness, isolation and car handling was required, culminating eventually in a sandwich bush that was flexible against shear but stiff in compression and tension. The car's subsequent resulting handling prompted automotive writers to describe the Europa as the nearest thing to a Formula car for the road.
Series 1
The Series 1 or S1 Europa was announced for sale to European markets on 20 December 1966. The first cars were delivered in France in February 1967. Volkswagen owned the rights to the Europa name in Germany, so cars for sale in Germany were badged Europe rather than Europa.The S1 was fitted with a modified Renault 16 1,470 cc straight-four engine and a four-speed gearbox. The engine was a special version. Lotus adapted the affordable but lightweight Renault engine and gearbox to the revolutionary Europa longitudinal mid-engined layout, inverting the gearbox's crown wheel on its pinion gear to avoid having four reverse gears. The S1 weighed. Autocar magazine achieved a top speed of, and recorded a 0-60 mph acceleration time of 9.3 seconds. Of particular note, in excess of 0.9 g lateral acceleration was consistently achieved by Car magazine on road tyres of that era.
Only 296 examples of the S1 were manufactured. These cars had extremely light and minimalist construction, with fixed side windows, fixed seats, no door handles, no internal door covers, and an aluminum dashboard. The steel chassis central beam was sandwiched within the fibreglass bodywork, thus reinforcing stiffness, but making repair rather complicated.
Series 1A and B had removable side windows, wooden dashboard, and internal door panel covers which could accommodate the windows once taken off. Series 1B had a redesigned rear panel, with new, rectangular light clusters.
Including the S1A and S1B variations, 644 Europa S1s were manufactured.
Series 2
The Europa Series 2, or Lotus Type 54, was introduced in April 1968. The S2 used the same 1,470 cc Renault engine and mechanical components as the earlier Series 1, but added a number of key refinements including opening electric windows, adjustable seats, a new fully carpeted interior and a polished wooden fascia panel for the dashboard. The most significant change was the switch from fully bonded construction to the use of bolt fasteners to attach the fibreglass body to the backbone steel frame. While reducing the torsional and flexural stiffness somewhat, the use of a separable body was welcomed by the automotive insurance industry as it greatly reduced the complexity and cost of making repairs to the vehicle.Early examples of the S2 were externally almost identical to the S1 with the exception of the new windows. From early 1969, secondary front indicator lamp nacelles were added between the headlights, and larger door handles were used in place of the S1's push-button items. During 1968 a number of Europas were produced bearing black-and-silver Lotus badges on the nose and steering wheel in place of the customary yellow-and-green ones. The official Lotus Cars website states these "black-badge" vehicles were to commemorate the death earlier in 1968 of Jim Clark, Lotus's champion Formula One driver, however this is debated by other sources.
Contemporary road tests for the Europa S2 recorded a top speed around 120 mph, 0-60 mph acceleration times of 9.3 seconds, standing 1/4 mile times of around 16.7 seconds, and an overall economy of around 30 mpg.
United States
A small number of Series 2 vehicles were modified to be "federalized" for export to the United States. These Federal Type 54s had the low front fenders of the European model and the larger 1,565 cc engine of the later Lotus Type 65. In 1969–70, the Type 65 was introduced specifically for export to the U.S., with additional changes to the body, chassis, suspension and the powerplant to better comply with U.S. D.O.T. standards. Among the changes, the engine was a slightly modified emission controlled Renault 16TL 1,565 cc unit rated at 80 hp rather than the 1,470 cc engine of the Type 54. The front suspension was changed to make the front end of the car taller along with taller front fenders to raise the headlamps. Road & Track magazine tested the Federal S2 and recorded 0-60 mph acceleration time of 9.6 seconds with a top speed of.In total, Lotus produced 3,615 Europa S2s.