By 1987, McLaren had found it increasingly difficult to compete with major manufacturer-backed teams while running a privateer engine financed by TAG and built by Porsche. For 1988, team principal Ron Dennis secured a supply of Honda's 1.5-litre V6 turbo engines, which had been the best power unit in Formula One since mid-1985. Honda had previously supplied Williams to their 1986 and 1987 Constructors' Championships but switched partnership to McLaren from 1988.
The 1988 season represented a transition year. Turbocharged engines were due to be banned from 1989, and the regulations were structured to reward teams that had already converted to naturally aspirated power — turbo cars were restricted to 150 litres of fuel per race distance while normally aspirated cars ran with no fuel limit. Despite this disadvantage, McLaren chose to continue with the turbo V6, which produced around 685 bhp, while Honda's engineers worked intensively on fuel consumption to avoid late-race retirements.
The MP4/4 was a fully new design, one of the few all-new cars on the 1988 grid. Its distinctive low-slung aerodynamics forced drivers into an almost reclined position — a reclining seating arrangement driven by the FIA's requirement that the top of a driver's helmet remain below an imaginary line from the roll bar to the bodywork cowling.
Senna was signed to partner Prost — at Prost's own suggestion — on a three-year contract. The partnership, combined with the Honda engine, immediately proved formidable. At the opening race in Brazil, Senna claimed pole position with Prost third, despite the car having had very limited pre-season testing.
The scale of McLaren's superiority was most vividly illustrated at the San Marino Grand Prix, the second race of the season. Senna and Prost both qualified in the 1:27s at Imola while no other competitor broke 1:30. Third-placed Nelson Piquet in the Honda-engined Lotus 100T qualified 3.352 seconds slower than Senna. Both McLarens lapped the entire field, including third-placed Piquet, by lap 55 of a 60-lap race.
Through the year, the MP4/4 sat on pole in 15 of 16 races — Senna taking 13 and Prost two — with only Gerhard Berger's pole at Silverstone preventing a perfect qualifying record. The car set the season's fastest speed trap at Hockenheim, where both Senna and Prost were recorded at 333 km/h. McLaren achieved ten 1-2 finishes and locked out the front row twelve times.
The only race the MP4/4 failed to win was the Italian Grand Prix at Monza. Senna was leading with two laps remaining when he collided with Jean-Louis Schlesser, driving a Williams in place of the chickenpox-stricken Nigel Mansell. With Prost already retired from a rare engine failure, Gerhard Berger won for Ferrari in an emotional result just a month after the death of Ferrari founder Enzo Ferrari. The car retired on four occasions across the entire season — Prost at Silverstone, Prost at Monza, and Senna at Monaco and Monza.
At the season's end, Senna claimed the Drivers' Championship ahead of Prost despite Prost scoring more total points. Under the season's best-11-scores rule, Senna's eight victories against Prost's seven proved decisive. In Portugal and Spain, Senna had been hampered by fuel readout problems and ran conservatively to finish sixth and fourth — both results he could drop from his tally under the scoring rules.
McLaren scored a then-record 199 points in the Constructors' Championship, finishing 134 points ahead of second-placed Ferrari and clinching the title with a 1-2 finish in Belgium, the 11th round of 16. The team achieved eight 1-2 finishes across the season and set a record for the highest percentage of laps led in a season, at 97.3 percent (1,003 of 1,031 laps).
Six MP4/4 chassis were produced from carbon fibre, with assistance from Hercules Aerospace, numbered 1 through 6. The Honda RA168E engine ran on a fuel blend supplied by Shell, consisting of approximately 84 percent toluene and 16 percent methanol for qualifying and a 60-40 blend for racing. Steve Nichols led a design team including Matthew Jeffreys, Dave North, Bob Bell, and others. A modified version designated MP4/4B was later used as a test mule for Honda's new 3.5-litre V10 intended for the 1989 season.
All six chassis survive. Chassis 1 and 6 remain with the McLaren Group; chassis 1 is normally displayed at the McLaren Technology Centre.
The MP4/4 was voted the greatest Formula One car of all time by a panel of Formula One engineers and designers, and the greatest racing car of the 20th century by Autosport readers. Its 15-from-16 win rate stood as the record for win percentage in a season until 2023, when the Red Bull Racing RB19 — also powered by a Honda V6 turbocharged engine — achieved a 95.45 percent win rate across 22 races. The car's dominance marked the high point of the turbocharged era in Formula One and remains the benchmark against which all subsequent dominant seasons are measured.