Honda was under much pressure in 2019 when it began to supply power units to Red Bull. Max Verstappen had won four grans prix the previous year, and Red Bull had claimed both the drivers’ and constructors’ titles four years in a row since 2010, while Honda, without a single podium finish in the four years since its return to F1, seemed to be an unworthy partner. For Honda, which has set its sights on winning the title rather than simply winning a grand prix, this was the perfect opportunity to set a high hurdle for itself in a battle where failure was not an option.

For Honda, the high-speed combustion adopted in the previous year’s RA618H Spec 3 was a major advantage which the RA619H inherited to achieve high output. The season started with both expectation and anxiety, with emphasis placed on strengthening each part of the car, including the frame, to withstand the engine’s high output and improving reliability.

The Red Bull RB15 was based upon the RB13, which was designed by Chief Technical Officer Adrian Newey and adapted to a wider body in 2017, and featured centerline cooling to slim down the overall width and refined aero rake development to efficiently generate downforce. Installing the Honda power unit, Red Bull prioritized power, making modifications to increase the size of the induction pods to allow more air flow. Improvements were made throughout the car to increase the efficiency of the intake, exhaust, and cooling systems and to help improve the performance of the power unit.

The RB15 featured a significantly improved front suspension. The concept of the Red Bull chassis was to have a large forward lean angle (rake angle), which controlled the downforce generated by the floor. The RB15 inherited this concept, while lowering the upper wishbone mounting to reduce nose dive under braking. This improvement was made to keep the clearance between the front wing and the road surface as constant as possible and to aerodynamically reduce the car’s jittery behavior. However, instability during cornering persisted as a major issue.

Honda, confident of the high power produced by high-speed combustion, and the durability and reliability of the car, introduced the Spec 3 engine in Round 8, France. Combustion was improved, and the compressor was updated, departing from a focus on reliability to once again pursuing higher power output. The Spec 3 was a failure in France as it could not cope with the extreme European heat wave, but after a short interval, the true value of the enhancements was demonstrated. Verstappen took a dramatic victory from behind in Round 9, Austria to give Red Bull Honda, and indeed Honda in its fourth F1 era, the first victory. The improved compressor gave the team a high altitude advantage, a major factor in this long-awaited victory for Honda.

Verstappen’s third place in the opening round gave Honda its first podium in its fourth F1 era, boosting its confidence in the power unit’s enhancements, and relief. However, despite consistently good results, the champions Mercedes were formidable, and victory remained elusive as mid-season approached. The RA619H Spec 3 was the breakthrough, and the team took three wins (Round 9, Austria, Round 11, Germany and Round 20, Brazil) for the season.

At the same time, the team was in a precarious situation. Pierre Gasly, promoted from Toro Rosso, was unable to recover from a serious crash in pre-season testing and was unable to adapt to the car’s instability, resulting in his move back to Toro Rosso in the first half of the season. Alexander Albon, who had just joined Toro Rosso, replaced Gasly at Red Bull, and although he drove well throughout the season, was unable to finish on the podium. Despite Verstappen’s consistent speed in a car that was considered to be hard to handle, it was a difficult season for Albon.

Verstappen won three races during the season, and in Round 12, Hungary, gave Honda its first pole position in its fourth F1 era. In Round 20, Brazil, Toro Rosso’s Gasly finished second after Verstappen, giving Honda power units a 1-2 victory. For Red Bull, Verstappen’s three wins, the same as the previous year, were considered the “minimum quota,” but for Honda, it was a season in which a high hurdle was overcome, and it could see the light at the end of the tunnel.