In 1984, when Honda gained its first win of its second F1 era, it was 6th in the constructors' standings with 25.5 points (McLaren TAG, the winner, had 143.5 points). In 1985, it was 3rd in the constructors’ standings with 71 points (McLaren TAG, the winner, scored 90 points). In just one year, the numbers showed that Williams Honda was on the move.

During this period, Williams, with Nigel Mansell replacing Jacques Laffite in 1985, had five wins, following McLaren and Ferrari. The number of strong finishes also increased, and the team was regularly on the podium. The Williams Honda FW11 was introduced in 1986, carrying on the momentum of the three consecutive wins recorded by the FW10 at the end of 1985. This was the car that brought Honda its first constructors’ title.

The construction of the car was typically Williams: conventional and faithful to the basics. The chassis was a full carbon monocoque, not the “temporary” structure of the early ‘80s with carbon panels pasted together, but a one-piece molded monocoque tub that took advantage of the material’s characteristics and manufacturing process. This was typical of Williams, which took the most realistic option for balancing performance and reliability, and this aspect served as the best test bed for Honda, greatly contributing to the development and refining of the engine.

The 1986 regulations reduced the amount of fuel during the race from 220 to 195 liters (refueling during the race was prohibited), and engines were now required to have excellent fuel economy as well as power. Honda, which advocates F1 as a “laboratory on wheels,” was more than pleased to meet the challenge. The results were evident: Williams Honda finished with 141 constructors’ points, while the closest rival, McLaren TAG, earned 96.

The technology of turbocharged engines was evolving remarkably, and Honda’s RA166E engine had reached a tremendous level of 1,000 horsepower per liter. This limitless increase in performance naturally became a concern for the FIA/FISA, and in 1986 the fuel tank capacity was decreased to 195 liters, and in 1987, maximum boost pressure was limited to 4 bar, which was further tightened to 150 liters/2.5 bar in 1988.

Even so, in 1986, Nelson Piquet, the new member from Brabham, won four races, and Mansell, the “Red 5” driver, won five, giving Williams Honda nine wins in 16 races, dominating the season to win the constructors’ title. The team was within striking distance of the drivers’ title, but after Frank Williams was involved in a car accident in early spring, the team was split between the Piquet and Mansell factions during the time he was absent. A dramatic turn of events in the final round in Adelaide, Australia allowed Alain Prost of McLaren TAG to take an upset victory. At the time, the points system was based on 11 races, so the final tally was 70 points for Mansell and 69 points for Piquet, with Prost taking the crown with 72 points. It was not enough, however, to claim both titles.

This incident may have had a lingering effect in 1987. Although Piquet won his first drivers’ title for Honda, in 1988 he moved to Lotus, and the Honda camp decided to part company with Williams, leaving with the drivers’ and constructors’ titles. This led to the McLaren Honda MP4/4, driven by Ayrton Senna and Alain Prost, undoubtedly a golden era for Honda.