In January 1992 Porsche A.G.’s Rolf Sprenger, head of the VR Department (which oversees the VRS or Exclusive Department), issued a memo to the Porsche Board of Directors regarding the building of a new project car the ‘911 Turbo RS Leichtbau’. The vehicle would be a lightweight street legal Turbo that would be different than standard Turbo units in regards to torque, horsepower, handling, visual aesthetics and market appeal.
There would be no limit on the build number but an expected 25-50 units would be produced. They would be sold through Porsche centers and importers at a price not to exceed 300,000 DM (paying a fixed sales commission of 10,000 DM). A 30,000 DM down payment would be required. The cars would be built and sold in the fiscal year ending July 1992. A prototype was built using a 1992 3.3 ltr Turbo chassis and the 1992 Turbo S Leichtbau was born.
On May 22, 1992 a memo was issued by Porsche A.G.’s VRS Department (also known as Exclusive) head Rolf Sprenger announcing that after consultation with then Porsche marketing chief Dieter Laxy, Porsche chief financial officer Walter Gnauert, and marketing heads for Germany and world export, Porsche would produce a limited edition ‘911 Turbo S Leichtbau’ with a planned production run of 80 units. Ironically production did not start until July 1992 ending in November 1992 so the ‘1992’ Turbo S Leichtbau was actually built in the 1993 model year.
The car was an expansion on the 1992 Turbo S2 which had won the 1991 and 1992 IMSA ‘Supercar Championship’, a series featuring near production equivalent cars. The goal was to increase engine output over the standard 3.3 turbo from between kW 24 (32 hp) to kW 39 (52 hp). In the end power was increased by kW 46 (61 hp) from kW 235 (320 hp) to kW 280 (381 hp). Weight was reduced from DIN empty weight of 1470 kg to DIN empty weight of 1290 kg a weight savings of 180 kg. Base price was 295,000 DM.
‘The Porsche 911 Turbo S – Lightweight can not only be driven in normal road traffic but is also extremely well suited for sport activities. The handling and the performance of the vehicle are particularly impressive in competition use.’, stated the factory technical bulletin Xe 6X013 dated 2/19/93. Unfortunately, the model was not destined for the U.S due to safety and emission standards.
The actual build numbers have been misquoted over time as a result of the May 1992 Rolf Sprenger memo stating 80 cars to be built and a subsequent lack of supporting records for the additional six cars which were also built and which brought the total to 86 cars (confirmed in the Porsche 911 History DVD in 2004). The 81st car was added on as part of the recorded end of production run on November 20, 1992. The 82nd – 86th cars lack definitive production information in the Porsche official records for their final production and delivery dates.
The unique rarity of this car was recognized by Porsche in 2011 as the 1992 Turbo S Leichtbau selected as one of very few models to go on display as part of the 25 Years of Porsche Exclusive event held at the Porsche museum in Stuttgart-Zuffenhausen, Germany. The event displayed the factory prototype car with the ‘Supercar Champion’ rocker script which was first introduced at the Geneva Motorshow debut in 1992.
The 1992 Turbo S Liechtbau took many weight loss cues from the base (non-touring) 1992 Carrera RS which was itself an extension of the Carrera Cup model. These cues include lack of under body protection and sound proofing, aluminum doors, lightweight luggage compartment lid, lack of rear seats, no A/C, and manual (no power) assisted steering. In fact the factory technical bulletin specifically refers to comparisons between the Leichtbau and the base (non-touring) version of the Carrera RS. Of course the ‘lightening’ process for the Liechtbau extended the base Carrera RS program to include ‘thin glass’, no airbag and stripped down trim and electronics.
According to the Porsche official site, ‘A weight saving of 180 kilograms was achieved through the use of lightweight plastic for the luggage compartment lid and the doors, thin glass for rear and side windows and the elimination of equipment details such as power windows, air-conditioner, central locking and even power-assisted steering.’
The official site continues to discuss its unique look, ‘This ‘Über-Turbo’ was given a distinctive visual impact by the side air intakes in front of the rear wheel openings, a flatter, body-coloured rear wing and air intakes to cool the brakes where the normal Turbo features fog lights.’
Of course the increase in power over the standard turbo and the X33 increased power option was an important part of the cars specification as was race car like handling. As stated by the factory, ‘With different camshafts, precision-machined intake ducts, slightly higher charge pressure and an optimised ignition and fuel injection system, this six-cylinder engine was capable of unleashing 381 bhp. To deliver all that power to the road surface safely, the car was lowered by 40 millimetres and the running gear was given firmer settings.’