Honda delivers first 2026 PU upgrade: Performance step forward but driveability issues remain unresolved

At Zandvoort, in a closed media session, Honda F1 technical director Yasuaki Orihara brought a piece of paper. He didn't talk about horsepower. He simply held up the paper as a way to deflect the question. It was a rare moment in F1: a chief engineer admitting that the first upgrade of the season had delivered the expected performance, but there was still a gap – a gap in driveability that the drivers were not yet satisfied with.

The upgrade was entirely focused on the internal combustion engine (ICE), with no changes to ERS, MGU-H, MGU-K or battery systems. This is fully consistent with the PU freeze regulations that came into effect in 2026, which only permit reliability and driveability updates. Honda has confirmed that dyno performance was replicated on track – meaning their development tools are working accurately for absolute metrics. But the driveability issue is a different story.

At Zandvoort, Aston Martin drivers Fernando Alonso and Lance Stroll reported that the PU still did not meet expectations in terms of feel. Specifically, the issues lie in combustion stability during braking phases, engine braking, and torque pickup when exiting corners. These are seemingly small factors but they determine the ability to extract maximum performance from a modern F1 car. And importantly: this is not just a PU problem. Mike Krack, Aston Martin team principal, emphasized that driveability is "also a chassis topic."

The truth is, any change in the chassis – especially Adrian Newey's first major upgrade package at Hungary – can alter the car's braking and cornering characteristics, thereby exposing or amplifying PU weaknesses. This is a multi-dimensional optimization problem that Honda and Aston Martin must solve together. And they have acted quickly: within 10 days after Zandvoort, engineers at HRC Sakura brought data and driver feedback to the dyno, developed countermeasures, and tested them ahead of Monza.

But is Monza really the final test? With its high-speed, low-downforce characteristics, Monza may not place as much stress on driveability as Zandvoort – which has many slow corners, banking, and elevation changes. If the countermeasures work well at Monza, it is only an initial positive signal. The real validation will come at tracks with similar characteristics to Zandvoort, such as Singapore or Suzuka.

Strategically, this upgrade is part of Honda's long-term plan to return as Aston Martin's works partner from 2026. The lessons on driveability – especially combustion control and torque calibration – will be directly applied to the new PU architecture. Honda is demonstrating that they can develop transparently and systematically, which is crucial for building trust with Aston Martin's engineering team.

However, risks remain. If the driveability issues persist across multiple race weekends, Aston Martin could lose points in the fiercely contested midfield. Moreover, diverting resources to fix the 2026 problem could slow 2026 PU development. But with the organized approach currently in place, Honda is showing they are ready for the future.

The question remains: will Monza be where we see a more refined Aston Martin PU? Or will we have to wait until the final races of the season? Let's wait and see.

In-depth analysis based on sources from Honda, Aston Martin, and technical reports. The author is an F1 tactical analyst with 12 years of experience, currently based in London and writing for the UK market.