Porsche 936

Porsche 936 /77 driven by Henri Pescarolo at 24 - hour race at Le Mans 1977

The Porsche 936 is a racing car from Porsche. The car built by the FIA regulations of group 6 was used in the World Sportscar Championship and the 24 Hours of Le Mans by the works team from 1976 to 1979 and 1981.

In 1976 Porsche with the 936 in parallel with the set up in Group 5 Porsche 935 both titles in the sports car and the manufacturers' world championship. In Le Mans racing car of 1976, 1977 and 1981, won the 24 - hour race.

In addition to the works team, the private racing teams Joest Racing and Kremer Racing built respectively on a 936 and started with it in the World Sportscar Championship, the Inter- series and in the German Racing Championship ( DRM) technology. By car, the Joest team won in 1982 with Bob Wollek the DRM songs.

• 2.2.1 body
• 2.2.2 Suspension
• 2.2.3 Engine and transmission

• 2.3.1 body
• 2.3.2 Suspension
• 2.3.3 Engine and transmission

• 2.4.1 body
• 2.4.2 Suspension
• 2.4.3 Engine and transmission

• 3.1 1976-1981 - successes in the World Sports Car Championship and Le Mans
• 3.2 1982 and 1983 - Appearances in the DRM
• 3.3 The results 1976-1984

• 6.1 Porsche database
• 6.2 Report on the Internet

General

For 1976, the FIA wrote next to the existing brand World Cup, started in the Group 5 cars, in addition, a World Sports Car Championship for Group 6 sports cars. Porsche originally planned only with the 935 to compete in the World Championship of Makes. However, the uncertainty about a future merging of the two racing series and also prestige reasons to operate not only in the supposedly easier Brand World Championship, led Porsche to develop a Group 6 cars. This decision was risky because of the development of the vehicle remained only a few months time. Therefore, the designers of existing and proven parts of other race cars like the Porsche 908/ 03, 917/10 and 911 Carrera RSR Turbo 2.1 served. The result was the Porsche 936 Spyder, the superior won the World Championship with five victories in seven races and was able to beat its main competitors Renault Alpine A442.

Porsche built the 936 total of three vehicles with chassis numbers 936001-936 003 Later, the private teams Joest and Kremer built two more cars with the numbers 936 004 and 936 005 on.

Model development

936 Spyder ( 1976-1981 )

Body

The body of the 936 was the 908/ 03 and 917/10 derived. About the aluminum space frame an aerodynamic plastic skin of polyester was attached. This consisted of the derived from the 908/ 03 front, marked with the flip-up doors and the central part of the 917/10 taken from the rear. The front had a large opening for the oil cooler and the feed lines for the ventilation of the front brakes in the middle. The headlights were installed behind transparent and integrated flush into the body of plastic discs. The two mirrors were initially mounted on two short rods on the front fenders.

The driver was sitting right in the two-seat cockpit in a bucket seat. In a few dashboard instruments were installed to inform the pilot of vehicle condition. Dominant was the great placed behind the steering wheel tachometer. The tail had a great two-piece and adjustable over the entire width extending wings. This was mounted on two fixed to the vehicle outer edge perpendicular fins. Additionally, the blade in the middle was supported. The engine was built after the mid-engine principle directly behind the cockpit. The transmission with limited slip differential was behind it.

In order to achieve an optimum air supply to the engine, Porsche tested different rear molds are mainly divided into the motor cover behind the cockpit. First, the developers opted for the flat shape, in which the body was taken directly above the engine and protect the pilots a roll bar was mounted behind the cockpit. At the 24 - hour race at Le Mans in 1976, Porsche is already the second wagon version with a raised engine cover and a large air scoop one. Starting in 1977, all 936 had an air inlet opening which served to improve airflow to the intercooler above the cockpit. Thus, the vehicle received a neutral handling, the fuel tanks, the preconceived maximum of 160 liters, left, right and installed behind the driver's cockpit were. The oil tank was located behind the pilot in the engine compartment.

1977 only engine technology, and the body of the 936/77 has been revised. In the wind tunnel, the developers improved the aerodynamic properties. The mirrors were mounted at the vehicle directly on the fenders and fitted with streamlined fairings. The rear end is already in use at Le Mans with the air scoop was taken over and enlarged the air opening. The length of the 936 was shorter by 50 mm and on the other hand been extended by 10 mm, the wheelbase. The track width reduced the technicians front by 50mm and rear by 30 mm. The weight remained unchanged at around 700 kg.

The 936/78 had a specially modified at the rear and sides of body. The car was with 4.96 meters approximately 800 mm longer than the previous two. The extended tail was strongly tapered towards the end. The on the outer sides bent down adjustable rear wing was mounted on two short fins, the inside rather than sat next to the outer sides. At both side faces in front of the rear wheel was again a large air opening for better cooling of the rear brakes. The gauges on the front and rear axle were increased again and were front and rear 1540 mm 1515 mm. In all subsequent vehicles, the developers took over these dimensions. The weight of the race car was around 780 kg. The body remained unchanged when it was launched in 1979 in Le Mans.

1981, Porsche 936 the last time in the 24- hour race at Le Mans. The 936/81 said carriage differed not optically from 936/78. The few changes were shortening the wheelbase and overall vehicle length by 10 mm.

Landing gear

The 936 had the front independent suspension with wishbones and Längszugstreben, rear wishbones, each with a longitudinal thrust strut up and down and progressively acting coil springs and Bilstein gas pressure shock absorbers.

The braking force distribution of a dual-circuit brake system could be adjusted depending on the driver and route. Round the car was equipped with internally ventilated brake discs and aluminum calipers.

All Versions vehicle drove forward to 10.5 J x 15 alloy wheels with 265/565 × 15 tires and rear to 15J x 15 alloy wheels with 340/600 × 15 tires.

Engine and transmission

In 936 an air-cooled 2.1 -liter six- cylinder boxer engine was installed in 1976, which was already used in the 1974 racing prototype 911 Carrera RSR Turbo 2.1. The engine had 6.5: 1, a low compression and performed together with a KKK turbocharger at 8000 rpm a power output of 382 kW ( 520 hp). In addition, a charge air cooler is installed per cylinder bank. Both coolers were placed longitudinally over the engine behind the horizontally mounted fan. The engine block was made ​​from lightweight magnesium. As with the 911 - series engines, the cylinder had two valves - one intake and one exhaust valve. The valve control carried out on a camshaft for each cylinder row, which was driven by a chain. In contrast to the motors of the Porsche 935 and 934, the engine had a double ignition in 936.

For the car in 1977 used the developers changed the turbocharger. Instead of a turbocharger for each cylinder bank, were now two turbochargers ( one per cylinder bank ) is used. Thus, the response of the engine could be improved and the performance by around 14 kW ( 20 hp) to 397 kW ( 540 hp ) will be increased.

1978 learned of the 2.1 -liter six- cylinder boxer engine, a fundamental revision. In order to control the thermal loading of the engine in a further increase in performance, the engine had a Luft-/Wasserkühlung. The valves were switched from two to four per cylinder. To the valve controller, the technician used two camshafts per cylinder bank, which have been driven through gears. This measure ranged air cooling of the cylinder no longer sufficient. Therefore, enhanced Porsche cylinder, where the cylinder heads were firmly welded to the cylinder body. The otherwise conventional engines needed and vulnerable in racing cylinder head gaskets accounted for. The cylinder heads have a water- cooling, where the cooling water was passed from the bottom upwards and outlet to the inlet side. For each row of cylinders one driven by the exhaust camshaft water pump was used. Since the fan only had to cool the cylinder, the diameter and the air flow rate could be reduced. By switching the engine cooling, the temperature decreased to the internally coated with Nikasil cylinders of 280 ° C when pure air-cooled engine to 200 ° C at wasser-/luftgekühlten engine.

The turbocharging with two turbochargers and intercoolers per cylinder line remained unchanged from the previous model year. However, the developers presented to the ignition system. Instead of the driven from the crankshaft ignition distributor ignition system was separated in an inductive and high voltage distribution. The so elaborately rebuilt engine produced at 8500 rpm maximum output of 426 kW (580 hp).

In 1979 the Porsche 936 almost one unchanged. The engine had the same performance as the 936/78. Only the fuel injection system was revised and provided a better pulling power of the engine at low speeds.

The last developed in 1981 by the Porsche 936 had also developed in 1978 engine with four- valve technology and the Wasser-/Luft-Kühlung. This engine was, however, developed for use in the so-called Indy - Porsche, which should start at the 500-mile race at Indianapolis. By increasing the engine capacity of 2.1 to 2.6 liter six-cylinder boxer engine delivered a maximum output of 455 kW ( 620 hp) at 8000 rpm.

The built behind the engine, five-speed transmission of type 917 was connected via a short shaft with the motor. To cool the transmission, a separate oil cooler is installed. All 936 had a limited slip differential to avoid spinning the wheels.

In 936/81, a four -speed manual gearbox was fitted with a limited slip differential instead of a five speed transmission. With this transmission, the racing car reached a top speed of about 360 km / h

Joest 936 Spyder Type 936/80 (1980)

Body

Reinhold Joest built in 1980 with his race team and with the support of Porsche in addition to the three factory cars a fourth on 936, which received the vehicle number 936 004. The body of the 936/80 referred to broadly in line with the 936/77. The most striking difference was the length of the vehicle, who was with 4960 mm round 810 mm longer than the car in 1977. The car had unladen weight of around 780 kg.

Landing gear

The chassis with wishbone front with Längszugstreben and wishbone rear with a longitudinal thrust strut up and down, as well as the progressively acting coil springs with gas pressure shock absorbers corresponded to the Porsche factory cars. Likewise, an identical dual-circuit brake system with internally ventilated brake discs and calipers used in aluminum.

Engine and transmission

While Porsche already provided for a new 2.6-liter six-cylinder boxer engine with Luft-/Wasserkühlung for the 936/81, built the Joest team 's proven air-cooled 2.1 -liter six- cylinder boxer engine from the 936/77 in the new constructed a vehicle. This engine produced with the two turbochargers and intercoolers at 8500 rpm maximum output of 426 kW (580 hp). With the five-speed manual gearbox, the car reached a top speed of 350 km / h

Kremer 936 Spyder Type 936/82 (1982)

Body

After Joest built with Kremer, a second private team on a 936. The 936/82 called car had the vehicle number 936 005 Porsche continued his works car no longer be a Kremer and presented the plans available. The private team asked many parts of the car such as the aluminum space frame, suspension parts and the tanks forth new. The body, which corresponded with the on the outer sides downward bent rear wing of the 936/78, was taken from the Porsche factory.

Landing gear

The chassis had to be produced by Kremer except the wheel hubs from scratch. The brakes and steering were still present at Porsche and were taken in 936/82 unchanged.

Engine and transmission

The biggest difference between the Kremer -936 and the Porsche factory car was its engine. While Porsche from 1978 began a turbocharged six-cylinder boxer engine with four- valve technology and a Luft-/Wasser-Kühlung, Kremer built in-house to an engine, as used in the Porsche 935. The only air-cooled 2.8 six-cylinder boxer engine still had the simpler two-valve technology. Due to the less complex design and cooling technology the car had fueled an approximately 40 kg lighter than the factory car and came in and ready to race to a weight of 800 kg. The five-speed transmission of type 917 with the limited slip differential was provided by Porsche.

Joest 936 Coupe Type 936 C ( 1982)

Body

Joest Racing built in 1982 designed by the group -6- 936 regulations in a Group C racing car with chassis number 936 005 to RJ. To obtain a group-C approval, extensive changes to the original Spyder were necessary.

The space frame has been adjusted to comply with the FIA regulations. The vehicle width increased from 1920 mm to 1990 mm and the length decreased from 4960 mm to 4800 mm. The height of the said carriage 936 C was 1000 mm, and had been reduced relative to the 936/80 to 170 mm.

The most noticeable change was the regulatory -related remodeling of the body from the open Spyder to a closed coupe. The vehicle weight increased by 780 kg to about 870 kg.

Landing gear

The chassis has not changed in the conversion and adopted by 936/80.

Engine and transmission

Used as motor Joest an air-cooled 2.5-liter six-cylinder boxer engine with two turbochargers. The cylinder had an inlet and an outlet, which were controlled by a camshaft per row of cylinders.

The engine produced about 411 kW ( 560 hp) at 8000 rpm. Together with the five-speed manual transmission reached the race car because of better aerodynamic properties with 360 km / h to 10 km / h higher top speed than the 936/80 Spyder.

Racing history

1976-1981 - successes in the World Sports Car Championship and Le Mans

The Porsche 936 was first used in 1976 for the 300 - km race at the Nürburgring and achieved with Rolf Stommelen a fifth. In the next round of the World Sportscar Championship Jacky Ickx and Jochen Mass piloted the car in the first place. Only in the 200-mile race at Mosport was a Shadow DN4 and a McLaren M20 finish the race before the 936. Porsche won with this successful series sovereign the World Sportscar Championship in 1976 and secured in parallel with the 935 title in the World Championship of Makes. In addition, Jacky Ickx and Gijs van Lennep won the 936 and the 24 - hour race at Le Mans, which was not counted at this time for the World Cup.

A year later, Porsche was able to repeat last year's success at Le Mans with the 936/77. The factory cars, piloted by Jürgen Barth, Hurley Haywood and Jacky Ickx, won after a hard race in which Ickx drove the past after a repair in last place car through large driving skills used on the first rank.

1978 Porsche came with the further developed 936/78 in Le Mans. The two factory cars used finished the race on the second and third place behind a Renault -Alpine A442B.

At the 24 - hour race at Le Mans in 1979 the factory team started as a Porsche Essex and not, as before over the years with the sponsor Martini. In the race, both secreted used 936/79 from. A car was taken out of the race early due to fuel supply and engine problems. For the second car, the race ended with a disqualification for unauthorized use of foreign aid.

1980 abandoned the Porsche factory team on a Le Mans start. It appeared there, however, the Joest Racing team with a newly built Porsche 936 /80. The under the name Porsche 908/80 propelled car was ranked second behind a Rondeau M379B.

Reinhold Joest won in the same year with the 908/80 at the Inter Series race at Most. The following year, Jochen Mass Joest with the race car drove for four runs in the Inter- series and achieved a second place in the season standings.

1981 Porsche came with the 936/81 again with the factory team at Le Mans. The distance traveled by Jacky Ickx and Derek Bell won ahead of two cars Rondeau M379C. This was the third Le Mans win a Porsche 936 and for the fifth Ickx Le Mans overall win.

After this race, Porsche the 936 is no longer in race one.

1982 and 1983 - Appearances in the DRM

In the World Sportscar Championship in 1982, the Joest team started with the built again after the Group 6 regulations Porsche 936 C. At the 6 - hour race at Silverstone and at the 1000 - km race at Mugello, the team could be the best result in each case celebrate a third place in the overall standings. In the season 1983, the private team played only two 1,000 -kilometer race at Spa- Francorchamps and Kyalami to the race car.

In addition to the Joest team also Kremer Racing had a 936 rebuilt. Both private teams continued their race car in 1982 in the German Racing Championship ( DRM) technology. There, dominated the 936 with a total of four wins and six second places the racing season. The starting for Joest Racing Bob Wollek won the DRM songs and Rolf Stommelen was with Kremer Racing vice-champion.

A year later only started the Joest team with the 936/80 and 936 C in the DRM and achieved with the drivers Volkert Merl, Leopold of Bavaria and Stefan Johansson multiple podium placements.

In the Inter Series 1982 Joest team drove the last time a full season with a 936 Bob Wollek won with the 936/80, four out of six races and finished the season with third place.

Had the last successful racing the 936 at the 300 - km race at the Nürburgring in 1984., Where Siegfried Brunn drove a 936 C to second place in the overall standings. With this race ended the nine-year history of the use of the successful racing car.

The results 1976-1984

Specifications

The Porsche 936 was produced from 1976 to 1982 and used in the following models: