Cars-Pickup-Truck: Porsche 961

วันอังคารที่ 10 เมษายน พ.ศ. 2555

>>Porsche 961

Porsche 961

Porsche 961

Development

In the early 1980s, the Fédération Internationale du Sport Automobile (FISA) reorganized their classification structure for motorsports. Two new categories, known as Group B and Group C, were designated for use in the World Sports-Prototype Championship. Porsche had developed the 956 for the Group C rules, and following the 956's debut, began work on developing a Group B car. A initial prototype concept, named the Porsche Gruppe B, debuted in 1983, after which plans were made to build the car for production and provide racing versions for customers as had been done with the 956.

By time the Gruppe B had been launched as the production 959 in 1985, Group B rules had been altered by FISA to better suit the class' use in the World Rally Championshiprather than the Sports-Prototype Championship. Plans to develop multiple customer cars for sports car racing were therefore scrapped by Porsche, but development continued on the production of car which could be factory run in order to put the car's development to use. This lone racing car, built on 959 chassis No. 10016, became known as the 961.

The new 961 retained much from the 959 road car, including most notably the four-wheel drive system that was uncommon in sports car racing at the time but allowable under the Group B regulations. The system was modified to distribution power more to the rear wheels rather than the balanced distribution of the 959. The driver adjustable damper and suspension systems were removed and replaced by a racing unit that could only be adjusted from by the pit crew, but was more reliable for endurance racing.

The 961's engine was a Porsche Type-935 unit. This twin-turbocharged engine was not only used in the 959, but was also the Group C 956 and later the 962C. This racing development helped the 961 run higher boost level than the standard 959. This resulted in a peak power output of 680 hp (510 kW). The brakes were also adapted from those developed for the 962C. Bodywork was replaced with lighter panels to bring the car down to a weight of 1,150 kg (2,500 lb), while the rear wing and front fascia were replaced with modified designs in order to create more downforce.Dunlop, who already supported Porsche's factory 962C team, supplied the tyres for the 961.

When the 961 was completed in 1986, Porsche had not yet built enough 959s to satisfy the Group B regulations for homologation.

Racing history

Making its first appearance at the May test for the 1986 24 Hours of Le Mans, the 961 was able to show its potential pace quickly by setting the tenth fastest lap time under the control of French driver René Metge. The 961's time was not only quicker than the BMW M1 which was entered in the Group B category, was also faster than several C1 and C2 class prototypes. At the race in June, Metge was joined by fellow Frenchman Claude Ballot-Léna and the two were able to qualify the car 26th. Through dependability the 961 was able to climb through the field as the race progressed and eventually finished the race in seventh place, 47 laps behind the winning factory 962C.

The Porsche 961 as it appeared for the 1987 24 Hours of Le Mans

Later in 1986, the 961 was moved to the United States and entered in the Camel GT Championship'sfinal round at Daytona International Speedway. The car was reclassified once again by International Motor Sports Association, this time being entered in the GTP category alongside sports prototypes like the 962. Drivers Kees Nierop of Canada and Günter Steckkönig of Germany were assigned to the car. The 961 however struggled with the banked turns of the Daytona circuit. The 961's Dunlop tyres were pushed beyond their limits and suffered several blowouts while the car was at full speed.This slowed the 961's overall pace down before it eventually finished the race in 24th position.

Porsche continued to develop the 961 into the 1987 season where it was prepared once more for Le Mans. The car was repainted in the colors of Rothmans to match the scheme used by the factory 962Cs. Performance fell from the previous year as the 961 earned only the 16th fastest lap in the May test session. Swiss driver Claude Haldi was assigned to partner René Metge, but the two were later joined by Kees Nierop whose 962C had been destroyed in a qualifying accident. Although the 961 managed to run as high as 11th overall in the race, Kees Nierop crashed the car after suffering a gearbox problem. The car was stopped and retired after it caught fire as Nierop attempted to return to the pit lane.

Following the Le Mans difficulties, and with no championship with which to run the 961 against similar machinery, the project was canceled.The 961, repaired after its crash and fire in 1987, now resides on display in the Porsche Museum in Stuttgart, Germany.

วันจันทร์ที่ 2 เมษายน พ.ศ. 2555

>>Porsche 930

Porsche 930

Porsche 930

Manufacturer	Porsche
Also called	Porsche 911 Turbo
Production	1975 – 1989 21,589 produced
Assembly	Werk Zuffenhausen, Zuffenhausen,Stuttgart, Germany
Predecessor	Porsche 911 Carrera RS 3.0
Successor	Porsche 964 Turbo (965)
Class	sports car
Body style	2-door 2+2 Coupé, Cabriolet, Targa, and Speedster
Layout	Rear-engine RWD
Engine	Single turbocharged and air-cooledflat-six; 3.0 (1975-1977) and 3.3 liters (1978-1989) 260 to 330 hp (DIN)
Related	Porsche 911, 934, 935, 959, 961,964

The 930 (usually pronounced nine-thirty) was a sports car built by Porsche, 930 actually being the "type number" for the pre-964 generation 911 Turbo produced between 1975 and 1989. It was Porsche's top-of-the-range model for its entire production duration and at the time of its introduction the fastest production car available in Germany.

Model history

Porsche began experimenting with turbocharging technology on their race cars during the late 1960s, and in 1972 began development on a turbocharged version of the 911. Porsche originally needed to produce the car in order to comply with homologation regulations and had intended on marketing it as a street legal race vehicle like the 1973 Carrera 2.7 RS. When the homologation rules changed, Porsche continued to develop the car anyway, deciding to make it a fully equipped variant of the 911 that would top the model range and give Porsche a more direct competitor to vehicles from Ferrari and Lamborghini, which were more expensive and more exclusive than the standard 911. Although Porsche no longer needed the car to meet homologation requirements, it proved a viable platform for racing vehicles, and became the basis for the 934 and 935 race cars. Ferdinand "Ferry" Porsche, who was running the company at the time, handed development of the vehicle over to Ernst Fuhrmann, who adapted the turbo-technology originally developed for the 917/30 CAN-AM car to the 3.0 litre flat-six from the Carrera RS 3.0, creating what Porsche internally dubbed as 930. Total output from the engine was 260 PS (191 kW; 256 hp), much more than the standard Carrera. In order to ensure that the platform could make the most of the higher power output, a revised suspension, larger brakes and stronger gearbox became part of the package, although some consumers were unhappy with Porsche's use of a 4-speed whilst a 5-speed manual was available in the "lesser" Carrera. A "Whale-Tail" rear spoiler was installed to help vent more air to the engine and help create more downforce at the rear of the vehicle, and wider rear wheels with upgraded tires combined with flared wheelarches were added to increase the 911's width and grip, making it more stable.

Early US-spec 930 - note
"Turbo Carrera" badging

Porsche badged the vehicle simply as "Turbo" (although early U.S. units were badged as "Turbo Carrera") and debuted it at the Paris Auto Show in October 1974 before putting it on sale in the spring of 1975; export to the United States began in 1976.

The 930 proved very fast but also very demanding. The 911 was prone to oversteer because of its rear engine layout and short wheelbase; combining those traits with the power of the turbocharged motor, which exhibited significant turbo-lag, meant driving the car required more skill to drive at the edge of its (higher) level of performance. Even though the rear engine layout provided superior traction, sudden bursts of power to the rear wheels in mid-corner could break the tires loose, causing the car to literally spin out of control. This effect was amplified if an inexperienced driver would instinctively lift the throttle in reaction. The vehicle needed to be kept at high revs during spirited driving to minimise the turbo lag. Skilled drivers quickly learned how to drive the 930 properly, and with that knowledge came the ability to drive the car above and beyond the levels of most other sports cars. Nevertheless, some fatal accidents caused by drivers outside their capabilities and traffic regulations resulted in product liability law suits brought against Porsche in the United States, where Ralph Naderhad made his name criticizing the rear engine-rear wheel drive layout of the Chevrolet Corvair.

Porsche made its first and most significant upgrades to the 930 for 1978, enlarging the engine to 3.3 litres and adding an air-to-air intercooler. By cooling the pressurized air charge, the intercooler helped increase power output to 300 hp (DIN); the rear 'whale tail' spoiler was re-profiled and raised slightly to make room for the intercooler. Porsche also upgraded the brakes to units similar to those used on the 917 racecar.

Changing emissions regulations in Japan and the U.S. forced Porsche to withdraw the 930 from those markets in 1980. It remained, however, available in Canada. Believing the 928 would eventually replace the 911, Fuhrmann cut-back spending on the model, and it was not until Fuhrmann's resignation the company finally committed the financing to re-regulate the car.

The 930 remained available in Europe, and for 1983 a 330 PS (243 kW; 325 hp) performance option became available on a build-to-order basis from Porsche. With the add-on came a 4-pipe exhaust system and an additional oil-cooler requiring a remodelled front spoiler and units bearing the add-on often featured additional ventilation holes in the rear fenders and modified rockers.

Porsche offered a "Flachbau" ("slantnose") 930 under the "Sonderwunschprogramm" (special order program) beginning in 1981, an otherwise normal 930 with a 935-style slantnose instead of the normal 911 front end. Each Flachbau unit was handcrafted by remodeling the front fenders. So few were built that the slantnose units often commanded a high premium over sticker, adding to the fact that they required a premium of up to 60 per cent (highly indivdualized cars even more) over the standard price. Several sources claim the factory built 948 units. The Flachbau units delivered in Europe usually featured the 330 hp (246 kW) performance kit.

928 sales had risen slightly by the 1985 model year, but there was still some question as to if it were truly capable of superseding the 911 as the company's premier model, and for 1986 Porsche re-introduced the 930 to the Japanese and U.S. markets, now featuring an emission-controlled engine producing 282 PS (207 kW; 278 hp). At the same time Porsche introduced the Targa and Cabriolet variants, both of which proved popular.

Porsche discontinued the 930 after model year 1989 when its underlying "G-Series" platform was being replaced by the 964. '89 models were the first and last versions of the 930 to feature the G50 transmission, a 5-speed manual transmission. A turbo version of the 964 officially succeeded the 930 in 1991 with a modified version of the same 3.3 litre flat-6 engine and a 5-speed transmission.

Performance

Model	0-60 mph	0–100 km/h	0–160 km/h (100 mph)	0–200 km/h	1/4 mile	1 km	Top speed
Performance data: Porsche 930
1975 930 260 hp	5.2 s	5.5 s	12.4 s	20.1 s	?	24.2 s	246 km/h (153 mph)
1978 930 300 hp	5.0 s	5.4 s	12.0 s	19.7 s	?	24.4 s	260.9 km/h (162 mph)
1983 930 330 hp Flachbau	4.7 s	4.85 s	?	?	?	?	275 km/h (171 mph)
1984 930 330 hp	4.6 s	4.8 s	11.6 s	17.7 s	?	23.8 s	278 km/h (173 mph)
1989 930 5-speed	4.9 s	5.1 s	12.0 s	20.4 s	13.6	24.6 s	260 km/h (162 mph)