The Lotus 56B is an evolution of the 4WD, Pratt & Whitney gas turbine powered Lotus 56 used in the Indianapolis 500 in 1968. One of the Lotus 56 chassis was converted to conform to Formula 1 regulations and christened the Lotus 56B. A new Pratt & Whitney engine (evolved from the Lotus 56 unit) was built for the car.
The Lotus 56B only had a handful of outings including three Grand Prix, the most successful being 8th (one lap down!) in the 1971 Italian Grand Prix at Monza piloted by Emmerson Fittipaldi. At best it was an experimental car, and was never seen as a replacement for the Lotus 72.
Although originally raced in Gold Leaf livery its last outing was in the gold/black livery of World Wide Racing in which it still resides...
Team Lotus 50th Birthday, Hethel Test Track, August 2004