Porsche 904

After having withdrawn from Formula One at the end of the 1962 season, Porsche focused again on sportscar racing. The 904 debuted late in 1963, for the 1964 racing season, as a successor to the 718, which had been introduced in 1957. Porsche designed the GTS variant to compete in the FIA-GT class at various international racing events. The street-legal version debuted in 1964 in order to comply with group 3 appendix J homologation regulations requiring a minimum of 100 road-going variants be sold by the factory. Porsche produced one-hundred and six 904s at four or five a day with a list price of US$7245 (FOB Stuttgart). Weber carburetors to generate from the four-cam engine. appearing more like a specialist racing car than the modified sports cars typical at the time, and was painted white. The fibreglass body was bonded to its steel chassis for extra rigidity, and achieved a drag coefficient of 0.34. The Type 771s, however, suffered a "disturbing habit" of making their flywheels explode. was given chassis numbers that began with the 906. Therefore, the car is also sometimes called the 906/8 Bergspyder, Later, the Bergspyder received again a lighter and rounded at the front and aerodynamically improved car body. A total of five copies were produced, of which three were destroyed in accidents. The 904 Bergspyder was replaced at the end of 1965 at the hill climb Ollon-Villars by the Porsche 906 Spyder Mountain. Suspension The chassis and suspension were taken over without major changes from the 904 coupé. The engine delivered up to 191 kW (260 hp) at 8,800 rpm and had a compression ratio of 10.5: 1. The car had a top speed of around 260 km/h (161 mph). ==Technical specifications==

• Engine (904 Coupé) • Drivetrain layout: mid-engine RWD • Engine type: flat-four • Bore × stroke: × • Displacement, ci/cc: 120/1966 • Compression ratio: 9.8:1 • Max SAE net horsepower: • Specific output, hp per liter: 100.7 • Weight to power, lbs per hp: 5.4 • Transmission: five-speed manual Performance • Drag coefficient: 0.34 • 0–: <6 seconds • Top speed: == Modern day replicas ==

Modern day replicas of the 904 are currently being produced by Chuck Beck in the US. == Racing ==

Making an inauspicious debut at Sebring in 1964, where it suffered clutch trouble, "a four-cylinder 904 took an astounding first overall" at the Targa Florio. It went on to a third at the Nürburgring and a perfect finish at Le Mans. Both times, all five starters finished, placed in the top twelve overall, among many much more powerful cars. 904s showed remarkable durability; they "almost always" finished, and at Reims in 1964, a customer car fresh from Stuttgart, driven to the track, went on to win without the need for any spares at all. For 1964, 904s racked up a 1–2 at the Targa Florio and class wins at Spa, Sebring (co-driven by Briggs Cunningham and Lake Underwood), the Nürburgring, Le Mans, Watkins Glen, Zandvoort, Canada, and the Paris 1000 Kilometer, in the process taking SCCA's C-Production and E-Sports Racing titles. In addition, it won rally events including the Tulip, Munich-Vienna-Budapest, Geneva, and "highly acclaimed" Alpine Rally. For 1965, results were "equally impressive", seeing wins at the Spanish, Rossfeld, Hellbronner, and Gaisburg rallies, as well as a class win and second overall in the Monte Carlo Rally which saw just 22 finishers in the points, out of 237 starters. In addition, 904s won their class at the Monza 1000 Kilometer, Targa, Spa, Daytona Continental, Le Mans, and Zandvoort, among others, repeating their E-Sports title win and adding an SCCA E-Production championship. == References ==