BMW has unveiled one of its hitherto secret supercar projects as part of the 25th anniversary celebrations of BMW's Technik GmbH subsidiary.
The Z29 prototype, completed in 2001, was a collaboration between Technik and BMW's M division.
The two-seater sportscar was designed to be as light as possible through the use of high-tech materials.
The centre section of the car - from the front bulkhead to the rear bulkhead was a monocoque made from carbon-fibre reinforced plastics. The front and rear subframes were made of aluminium. The final prototype weighed just 1166kgs.
The Z29 was powered by the then-current 336bhp straight-six engine used in the M3, which gave the car a 0-62mph sprint time of just 4.4 seconds.
The Z29's unusual scissor doors never made it onto a production car, but the Z29 is said to have influenced the 2006 M Roadster.
However the project had its biggest influence on the 2004 M3 CSL, which used carbon-fibre, reinforced plastics for the roof panel, as well as various other body mouldings including the front bumper.