The aluminum body design of the Porsche 550 was inspired by the special race cars from the successful Glockler team, which had won the 1950 German Sports Car Championship in the 1.1 liter class. The design process started in the October of 1952 and in 1953, Porsche mechanics working in Zuffenhausen created two prototypes of a new design for Porsche –the type 550 – with the help of Wiedenhausen Karosserie in Frankfurt who had built the Glockler bodies. The first type 550s were ready to debut on 31 May 1953 at the Nurburgring. In early 1954, production of the prototypes expanded. The production of type 550-07, which was also known as the Buckelwagen, was given to Wendler to demonstrate their coach building skills to Porsche, trying to secure the contract for the rest of the type 550 production builds.
Porsche assigned build numbers to each of the 550/1500RS cars built (RS short of rennsport which is ‘racing’ in German), with the prototype starting with 2-digit chassis numbers, 550-01 through to 550-14. The first “production” 550 was assigned a 4-digit chassis number, 550-0015 with the last “documented” Spyder as 550-0090.
After the first eight prototypes were completed, the race department took delivery of the remaining Karosseriebau Weinsberg designed frames. It kept seven aside for its own uses, additional development prototypes and Le Mans race cars. Shortly after, the factory had decided that the complicated assembly techniques of the Weinsberg designed Spyders would cause delays in the production of the allocated ‘customer’ cars that were to be built. Wendler Karosserie in Reutlingen was given the Porsche contract to build the remaining customer bodies based on the Weinsberg frame, but they were slightly restyled by Erwin Komenda, resulting in lower fenders than the previous prototypes and also utilized the slanted front headlights from the 356. The customer Spyders weighed about 590 kg, not quite 60 kg more than the previous factory cars. Wendler was contracted to build 69 cars for private customers, of which 33 were destined for the US market.
There are a number of inconsistencies in the Wendler builds, such as, chassis 550-0022 was mated with the body of 550-0020, which left the chassis of 550-0020 as a frame only build. It is believed a new body has recently been fabricated to fit the original chassis frame. The fitting of the type 547 engines were also out of sequence with P 90 001 mated with 550-0016, P 90 002 with 550-0018 and P 90 003 with 550-0017. All other quad cams were randomly fitted to chassis throughout the series.
There is now discussions that Wendler did not build any of the prototypes and that Weinsburg actually made all the frames through to 550-0042. The Wendler frames started with 550-0043 for the re-build of Annie Bousquet’s 550-07 car which had been rebodied on the spare frame. After her fatal accident, Porsche rebuilt the car, sold it to Blendl and it burned. The remaining 550-0043 frame was never really a car.
The Porsche team found that the upgrade to bigger 60mm front brakes in the later builds caused a lot of stress on the frame through flexing with a high chance of the main cross member breaking away. From build 550-0076 there was a modification in the chassis design with the addition of high rail bracing. Two previous builds were also updated – 550-0032 and 550-0048.
After a total of 90 builds of the type 550, Porsche was back to the drawing board developing the type 550A of which 40 were built. It is documented that two more 550s were built as special orders after production finished – 550-0091 and 550-0093.
FB fixed back
LB lift back
RTB rear torsion behind axle
RTA rear torsion ahead of axle
FOT frame over trans
FUT frame under trans
Body type: Buckelwagen (Proto No 1) – LB, RTA, FUT
Chassis numbers: 550-05
Coach builder: Weinsberg/Porsche
Quantity built: 1
Body type: Buckelwagen (Proto No 2) – LB, RTA, FUT
Chassis numbers: 550-07
Coach builder: Porsche/Wendler
Quantity built: 1
Body type: Customer – LB, RTA, FUT
Chassis numbers: 550-0049 to 550-0090
Coach builder: Wendler
Quantity built: 42