Cars-Pickup-Truck: >>Lotus 91

Lotus 91
Category	Formula One
Constructor	Lotus
Designer(s)	Colin Chapman; Martin Ogilvie
Predecessor	87B
Successor	92
Technical specifications
Chassis	Carbon fibre and Kevlarmonocoque
Engine	Cosworth DFV, 2,993 cc (182.6 cu in), 90° V8, NA, mid-engine, longitudinally mounted
Transmission	Lotus / Hewland 5-speed manual
Fuel	Valvoline
Tyres	Pirelli; Goodyear
Competition history
Notable entrants	John Player Team Lotus
Notable drivers	11. Elio de Angelis; 12. Nigel Mansell; 12. Roberto Moreno; 12. Geoff Lees
Debut	1982 Brazilian Grand Prix
Constructors' Championships	0
Drivers' Championships	0

The Lotus 91 was a car used by the English team Lotus in the 1982 Formula One season, designed by Colin Chapman, Martin Ogilvie and Tony Rudd. After several uncompetitive seasons with experimental or mediocre cars, Colin Chapman went back to basics and designed the graceful Lotus 91, based in part on the Williams FW07 and Lotus' own 88 design. Powered by the Ford Cosworth DFV, and using a standard Hewland gearbox, the 91 was uncomplicated and easy to maintain. Following Brabham's lead, the new car was the first Lotus chassis to use carbon brakes, improving braking performance considerably.

After a design study by Chapman into new composite materials, the decision was taken to build the car in carbon fibre, making it after the McLaren MP4/1 the second F1 car to race to be built from the material - the Lotus 86/88 not having raced because it was banned.

Under the direction of Peter Warr, the team worked hard to make the car as competitive as possible. The lightweight chassis gave the 91 a fighting chance against the far more powerful turbo engined cars, and Cosworth worked on a short stroke version of the DFV purely for Lotus' use. The suspension was revolutionary. Using an on-board system to control the ride height and behavior of the suspension, the Lotus 91 was the first car to be fitted with active suspension. The system was partially controlled by computers, but at this early stage was mostly operated by hydro-pneumatic valves. Elio de Angelis used the car well, but found the 91 was mostly competitive on ultra fast tracks like Hockenheim, Monza and the Österreichring. The latter track provided a thrilling final lap win for De Angelis against Keke Rosberg in the Williams. That as well as several other podium places helped the team to fifth in the final standings in 1982, before ground effects were banned for the 1983 Formula One season, and the 91 was replaced by the first Lotus turbo car. The 91 was the last Lotus F1 car to win a race under Colin Chapman's rule before he died of a heart attack on 16 December 1982.

This was the last Formula One car until 2015 to run on Valvoline fuel.