McLaren MP4/2

The chassis was designed by John Barnard together with Steve Nichols, Gordon Kimball, Alan Jenkins, Tim Wright, and Bob Bell. It used an all-carbon fibre monocoque, a technology Barnard had pioneered with the predecessor MP4/1. The car was powered by a 1.5-litre 90° V6 TAG-Porsche turbo engine funded by TAG Electronics and designed by Hans Mezger at Porsche. That engine had first been raced in the 1983 Dutch Grand Prix at the insistence of Niki Lauda, who wanted race miles on it before a full championship assault.

In 1984 the engine produced approximately 650 bhp in race trim and up to 800 bhp under maximum qualifying boost. By 1986 race output stood at around 850 bhp, below the 900 bhp of rival Honda, Renault, and BMW units. The car was among the few of its era to run carbon brakes, an advantage on most circuits; at hot street circuits such as Detroit and Dallas, steel brakes from competitors lasted longer. Aerodynamic efficiency and excellent rear-end traction made the MP4/2 especially dominant on high-speed circuits composed of long, fast corners — Jacarepaguá, Silverstone, Spa-Francorchamps, Zandvoort, Kyalami, the Österreichring, and Dijon. The car was designed to exploit the 220-litre fuel limit in effect for 1984 and 1985; for 1986 the limit was reduced to 195 litres.

For the 1985 MP4/2B, aerodynamics were cleaned up and rear winglets banned by new regulations were removed. The suspension was redesigned after McLaren switched from Michelin to Goodyear tyres when Michelin withdrew from Formula One. For the 1986 MP4/2C only minor aerodynamic changes were made.

Alain Prost joined Lauda for 1984. Prost had narrowly lost the 1983 championship to Brabham's Nelson Piquet by two points after Renault fired him following the season. McLaren boss Ron Dennis signed Prost in place of John Watson, reportedly after contract talks with Watson broke down over salary. The MP4/2 scored 12 wins in 1984, at the time the highest by a single team in a season. Piquet's Brabham BT53-BMW took nine pole positions in the year, often outpacing McLaren in qualifying, but the McLarens were the most reliable and consistent cars. The team failed to finish only twice — in Belgium and Dallas — and recorded four 1-2 finishes: South Africa, Germany, Holland, and Portugal.

Lauda beat Prost to the Drivers' Championship by half a point in the final round in Portugal, the closest margin in Formula One history, despite Prost winning seven races to Lauda's five. McLaren won the Constructors' Championship with 143.5 points to Ferrari's 57.5. The four races the team did not win went to Piquet (Canada and Detroit), Keke Rosberg (Williams-Honda, Dallas), and Michele Alboreto (Ferrari, Belgium at Zolder).

At the season-opening South African Grand Prix at Kyalami, a warm-up crash involving Piercarlo Ghinzani's Osella-Alfa Romeo granted McLaren extra time to fix an electrical misfire in Lauda's car; without that delay, Lauda would have been forced to take the spare, leaving Prost — whose own car had suffered a fuel pump failure — without a car. Prost started from the pit lane in the spare and finished second on the lead lap.

The MP4/2B's primary competition came from Michele Alboreto in the Ferrari 156/85, who challenged Prost for most of the season until Ferrari's reliability deteriorated in the second half. Prost won five races and clinched the title with two rounds remaining by finishing a calculated fourth at the European Grand Prix at Brands Hatch. He became the first French driver to win the World Drivers' Championship. McLaren won its second successive Constructors' title with 90 points to Ferrari's 82.

Lauda retired at the end of the season after adding a final victory at the Dutch Grand Prix at Zandvoort, where he beat Prost by 0.232 seconds. McLaren operated without team orders requiring one driver to yield to the other, only that they should not collide.

Lauda's place was taken by Keke Rosberg, the 1982 World Champion. Rosberg's heavy-braking, ground-effects-era style was not suited to a car Barnard had optimised for the smoother inputs of Prost and Lauda. Before mid-season, Barnard refused to let Rosberg alter his setup; by the time he relented, Rosberg had already announced his retirement from Formula One prior to the German Grand Prix at Hockenheim. Only at Hockenheim, with setup changes permitted, did Rosberg qualify on pole.

By 1986 the Williams FW11 had become the faster car, driven by Piquet and Nigel Mansell. Prost secured four wins and his second consecutive Drivers' Championship at the season-ending Australian Grand Prix after Rosberg, then leading, suffered a tyre failure on lap 62, and Mansell had an identical failure one lap later at approximately 180 mph on the Brabham Straight. Piquet, who had inherited the lead, pitted for tyres and handed the lead to Prost. It was the first back-to-back championship since Jack Brabham won in 1959 and 1960.

Across three seasons the MP4/2 family won 22 Grands Prix (Prost 16, Lauda 6), took 7 pole positions (Prost 6, Rosberg 1), and accumulated 327.5 championship points. The car contributed to 2 Constructors' Championships and 3 Drivers' Championships. All three variants won at the Österreichring in successive years (1984, 1985, 1986). Prost's MP4/2C was driven at the 2010 Goodwood Festival of Speed by 2009 World Champion Jenson Button, who had joined McLaren that year. At the 1986 Portuguese Grand Prix, Rosberg's MP4/2C carried a yellow Marlboro logo to promote Marlboro Lights.

This article is based solely on the supplied corpus. No external sources were consulted; claims that could not be substantiated against the corpus were omitted under the drop-the-claim rule.