Honda’s chief engineer, Shintaro Orihara, has detailed modifications to the manufacturer’s B-spec power unit, set for its competitive debut with Aston Martin at the upcoming Dutch Grand Prix. The engine upgrades focus on enhancing combustion efficiency and reducing internal friction.
Orihara confirmed that changes include a revised pre-chamber design and altered piston geometry. These modifications are intended to accelerate the combustion process within the engine, aiming for a performance breakthrough.
Further refinements have been made to the lubrication systems. These adjustments are designed to minimise frictional losses, thereby contributing to overall engine efficiency and power delivery.
Despite reports suggesting a significant 50bhp gain, Orihara cautioned against such figures. He stated, ‘I want to have that number, but that is a quite big number.’
Orihara added, ‘I can’t describe the detail of power, but my feeling with that is just, no, I don’t think… not the real number.’
However, Honda has successfully met its internal development targets for this specific engine upgrade. This marks a crucial step for the power unit supplier and its partner team.
The B-spec engine will be introduced at the Dutch Grand Prix, scheduled for August 21-23, 2026, at Circuit Zandvoort. This event follows the Formula 1 summer break, marking the resumption of the season.
Aston Martin previously ran the new Honda power unit during a filming day at the Hungaroring. This session occurred in the days following the Hungarian Grand Prix, where the AMR26 chassis debuted its own 16-part upgrade package.
The Aston Martin Aramco F1 Team’s AMR26 chassis showed improved performance during its Hungarian Grand Prix debut. The focus now shifts to the combined package with the updated Honda power unit.
Orihara also commented on the evolving relationship between Aston Martin and Honda. He noted that the collaboration has strengthened through challenging periods during the current season.
We have developed our relationship between Aston Martin Aramco and Honda. Not only trackside, but also on the factory side. Our relationship was good at the beginning, but also through the tough moments, our relationship has been built up through the season, and now I think we are in quite a good position in the relationship.
The partnership, which experienced a difficult start to the 2026 season, appears to be building momentum. The upcoming Dutch Grand Prix will provide the first competitive assessment of the new engine specification.