Top gear old are testing Porsche 959 and the new Porsche turbo
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Tiff Needell are testing the porsche 959 and a Porsche turbo old. The Porsche 959 was a sports car manufactured by Porsche from 1986 to 1989, first as a Group B rally car and later as a legal production car designed to satisfy FIA homologation regulations requiring that a minimum number of 200 street legal units be built.
During its production run, it was hailed as being the most technologically advanced road-going sports car ever built and the harbinger of the future of sports cars: it was one of the first high-performance vehicles to use an all-wheel drive system; it provided the basis for Porsche's first all-wheel drive Carrera 4 model; and it convinced Porsche executives of the system's viability so well that they chose to make all-wheel drive standard on all versions of the 911 Turbo starting with the 993 variant. During its lifetime, the vehicle had no other street legal peer. The 959's short production run and performance have kept values high.[citation needed] In 2004, Sports Car International named this car number one on the list of Top Sports Cars of the 1980s
Development of the 959 (originally called the Gruppe B) started in 1981, shortly after the company's then-new Managing Director, Peter Schutz, took his office. Porsche's head engineer at the time, Helmuth Bott, approached Schutz with some ideas about the Porsche 911, or more aptly, a new one. Bott knew that the company needed a sports car that they could continue to rely on for years to come and that could be developed as time went on. Curious as to how much they could do with the rear-engined 911, Bott convinced Schutz that development tests should take place, and even proposed researching a new all wheel drive system. Schutz agreed, and gave the project green light. Bott also knew through experience that a racing program usually helped to accelerate the development of new models. Seeing Group B rally racing as the perfect arena to test the new mule and its all wheel drive system, Bott again went to Schutz and got the go ahead to develop a car, based on his development mule, for competition in Group B.
Porsche began with an engine they already had, and moved on with development from there. The powerplant, a twin-turbocharged boxer six-cylinder engine with an air-cooled block and water-cooled heads, displaced 2.85 liters, about half a liter less than a contemporary 911 engine. The motor had originally been developed for the "Moby Dick" race car and then been redeveloped slightly for the short-lived Porsche Indy Car and several other projects before being "tweaked" a last time for use in the 961, the 959's racing counterpart. The water-cooled cylinder heads combined with the air-cooled block, 4-valve heads and sequential turbochargers allowed Porsche to extract 331 kW (444 hp) from the compact, efficient and rugged power unit.[3] The use of sequential twin turbochargers rather than the more usual identical turbochargers for each of the two cylinder banks allowed for smooth seamless delivery of power across the engine RPM band, in contrast to the abrupt on-off power characteristic that distinguished Porsche's other turbocharged engines of the period. The engine was used, virtually unchanged, in the 959 road car as well.
In an attempt to create a rugged, lightweight shell, Porsche adopted an aluminium and Aramid (Kevlar or Twaron) composite for body use along with a Nomex floor, instead of the steel normally used on their production cars[4]. The vehicle's weight of 3,190 pounds (1,450 kg) helped to achieve its high performance level.
2.85-l-Biturbo-Engine
Porsche also developed the car's aerodynamics, which were designed to increase stability, as was the automatic ride-height adjustment that became available on the street car (961 race cars had fixed suspensions). Its "zero lift" aerodynamics were a big part of keeping it drivable.[citation needed] The 959 also featured Porsche-Steuer Kupplung (PSK) which was at the time the most advanced all-wheel-drive system in a production car.[citation needed] Capable of dynamically changing the torque distribution between the rear and front wheels in both normal and slip conditions, the PSK system gave the 959 the adaptability it needed both as a race car and as a "super" street car. Under hard acceleration, PSK could send as much as 80% of available power to the rear wheels, helping make the most of the rear-traction bias that occurs at such times[5] It could also vary the power bias depending on road surface and grip changes, helping maintain traction at all times. The magnesium alloy wheels were unique, being hollow inside to form a sealed chamber contiguous with the tire and equipped with a built-in tire pressure monitoring system
