The car, designed by Colin Chapman, Martin Ogilvie, Peter Wright and Tony Rudd, was an attempt to take ground effect as far as possible.

An additional ground effect system was built into the nose, in an effort to turn the whole chassis into an aerodynamic device.

In theory this would create a tremendous amount of downforce, so the chassis would have to be built to be more structurally rigid than that of the Lotus 79.

The phenomenon was known as porpoising, as the car appeared to be lifting and squatting at different speeds, causing it to lurch violently through corners.

Andretti persevered with the car, but his new teammate Carlos Reutemann refused to drive it and stayed with the Lotus 79.