In 1982, Ferdinand Piëch signed an agreement with Aluminum Company of America. The objective was to design and develop a car that would be substantially lighter than any other vehicles in its class (to compensate for the fact that standard all-wheel drive was around 100 kg (220 lb) heavier than competitors' rear-wheel drive). In the late 1980s, it was decided that the target vehicle would be a successor to the V8 (Typ 4C) flagship introduced in 1988. By 1990, a final design by Chris Bird and Dirk van Braeckel was chosen and frozen for series production in mid-1991. In September 1993, the Audi Space Frame (ASF) Concept was unveiled at the 1993 Frankfurt Motor Show (IAA) as a D2 Typ 4D prototype in polished aluminum. Pilot production began in December 1993 and development ended in early 1994, at a total cost of $700 million (£418.1 million).