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Constructor Porsche AG
Chassis Steel bodyshell with reinforcements, added fiberglass wheelarches.
Body Steel doors, hood and engine cover.
Suspension McPherson strut at front, semi-trailing arms rear, coil springs. Lower wishbones, longitudinal torsion bars, Bilstein shock absorbers, anti-roll bar
Gearbox Porsche synchromesh 4speed.
Wheelbase : 2270mm
Front track 1565mm
Rear track 1539mm
Engine Flat 6, air-cooled 2993cm3. Fuel injection via Bosch K-Jetronic mechanical. Type 930/71 B 6. 2 valves / cylinder, SOHC.

The Porsche 934 was the turbo version of the Carrera, and also the race version of the 930. It was introduced in 1977, after being somewhat banned for the 1976 season. John Bishop could no longer allow his series to lose top competitors. The car weighed around 1120kg, this was because the Typ 930/50 3-litre motor that had been homologated in the H-series 911 Turbo was classed on the basis of its swept volume equivalency of more than 4-litres. The car was delivered to its customers with electric windows, as Porsche had no reason to lighten the car, which was to be close to the road going version : the 930. A rollcage was used to strengthen the package. 934s were equipped with fully-adjustable suspension and anti-roll bars plus cross-drilled and ventilated discs with finned calipers. The rear spoiler was used to duct air to the transmission oil cooler and the turbo. Large aluminum rollcage for stiffness, standard cut-off switch to the electrical system mounted on the dashboard, air dam with a large cut to allow air incoming to the huge oil radiator, on either side are the brake cooling ducts, and along them, the intakes to the radiators of the intercooler, two water radiators were fitted into the front spoiler. The engine featured the racing flat fan for air cooling distribution. Two small water radiators pumped the water around the system. Smaller wheels, as well as the small tail made the car much more difficult to drive than the 935. 31 934's were built, but even as early as spring 1976, the factory were providing owners with the opportunity to transform their vehicles into 934/5's. The 934s were allowed in IMSA in 1977, with the mechanical fuel injection of the 935. HP raised to 600. Lighter weight and 15inch wheels. Much bigger rear wing. Bosch mechanical twin row plunger type fuel injection pump from the 935 engine. This could be done either by Porsche or the privateer teams themselves, the 934/5 upgrade pack including wider wheels and a split-level rear wing normally good for a couple of seconds per lap. In 1979 however, the car was to be entered in GTO, and win some races, but the additional aerodynamical components had to be removed. The cars would evolve later, and in 1983, a special version of that car won the 12 Hour of Sebring race. The cars could use a single plug engine, bigger wheels and a huge tail. They would be used until 1987 or so, and sometimes replaced by the 930S, which featured a slant nose, à la 935.

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