The power unit produced by Honda F1 has now been successful until it has won a double title under the name of Red Bull, and it is eager to return to F1 in 2026. However, Honda’s fourth F1 activity, which started in 2015 to revive the legendary McLaren Honda, started with a big setback.
Honda’s engine performance in 2015, his first year back in F1 with McLaren, was so bad that it put the entire program in jeopardy.
It was an embarrassment for Honda F1 and a frustrating technical breakdown for McLaren, ultimately damaging their relationship for a long time and leading to a major breakup.
McLaren F1 driver Jenson Button and new hire Fernando Alonso battled for Q1 qualifying all season long, with the car averaging around 2.7 seconds behind the leaders from qualifying pace and the team barely outperforming low-budget Manor. , sank to 9th place in the Constructors’ Championship.
The technical cause of the disaster was a dramatic lack of power that took more than half the season to figure out. One of the reasons for this is that it was very unreliable in the early days, requiring the engine to run at significant de-runs to keep temperatures under control.
But there was a political backstory behind the technical problems. Basically, McLaren’s Ron Dennis, eager to progress from Mercedes’ customer team status as soon as possible, has put pressure on Honda to enter a year earlier than he originally planned. In addition, a set of highly ambitious goals have been jointly agreed between the two partners.
Given the complexity of engines in the hybrid era, the extremely tight packaging ultimately limited the potential for power unit development with McLaren’s ‘size zero’ concept. It was a storm of adversity that began with a series of repeated failures of the ERS-K seal during winter testing, which drastically shortened the test mileage. Even after that problem was resolved in time for the first half of the season, the ERS could not be used at maximum power etc. without serious overheating problems.
At this stage, McLaren and Honda F1 have put a brave face on things, emphasizing how new the project is and noting that it is essentially two years behind the other power unit makers’ development curves. I did my best to point it out.
Fitted with a Honda RA165H power unit, the McLaren MP4-30 was first conceived by former Red Bull aero boss Peter Prodromou. It has a very different aerodynamic philosophy than previous McLarens and Jenson Button was very positive about the overall balance.
“It has a great front end,” said Jenson Button.
“If you turn in, add steering lock and you have more front end, it’s always a great place and that’s what we try to achieve in every debriefing session.”
“Previously, the McLarens with Pirelli, even the fast ones, had a big front end on the first turn-in, a little rear movement and understeer at the apex. This is very sweet with no understeer. It’s a feeling.”
“You can brake well and you can be confident that you are stable through the corners.”
However, McLaren Honda was 5.1 seconds behind the pace setter at Albert Park, which was the stage of the opening round F1 Australian GP.
A key part of the concept to achieve the engine’s ambitious downsizing was to mount the turbo’s compressor within the V of the engine. Not only did this give a smaller rear overhang than the traditional Ferrari/Renault turbo placement (which opened up space for aerodynamic development), but it also placed the compressor at the front of the engine just behind the cockpit. There was no need to mount the engine further back like the Mercedes split-turbo concept it was fitted with.
Honda F1’s solution was the best in terms of layout compactness. But it brought an insurmountable problem.
The compressor was smaller than its rivals to fit in the V. In theory, you could compensate for this by just turning it faster and giving it the same boost. But in reality it didn’t work.
Initially, the MGU-H, which ran on the same shaft as the turbo, could not operate at the required speed due to vibration problems. This put an artificial limit on the speed of the compressor. The small, slow-rotating compressor significantly dampened the engine’s power.
It was assumed that once the vibration problem was resolved and the turbo’s compressor could run at design speed, the engine would suddenly become competitive, or at least close to it.
But that didn’t happen. As the compressor speed increased and frictional resistance increased, its energy inefficiency decreased. The balance point between more compressor boost and the resulting increase in pressure from the exhaust made for a very modest point of power upgrades. This limited the amount of power that could be supplied to the ERS loop.
As such, the battery could not be recharged as quickly as other power units. At Spa-Francorchamps, for example, Jenson Button and Fernando Alonso only allowed him to use an extra 160bhp of electric boost on one of his two straights. There were sections of the entire lap where other cars were behind him by 200bhp.
Yasuhisa Arai, Honda F1’s project leader at the time, said, “In the middle of the season in August, we realized our weakness in a more concrete way. The weakness of the package was the deployment of the MGU-H and ERS. “I understood, but I was having trouble identifying the cause. Fortunately, in August, everything came to light and the situation was completely rectified.”
“This finding had a big impact on us as we realized that we needed more energy to actually use the deploy in racing and testing. And it’s very difficult to change everything because I don’t think you can change it in the middle of the season, so we were aware of it, but we couldn’t change it.”
Eric Boullier, McLaren’s F1 team principal at the time, barely hid his frustration at Monza.
The issue was compounded by the engine swap restrictions of the time, but in essence, the size zero concept was fundamentally wrong, and got worse and worse as time went on.
The optimum size of turbos in Formula 1 has grown as the efficiency of power electronics and MGU-Ks has increased rapidly through development. The more efficient it got, the bigger the turbo size it could justify. Already by 2015, the optimal size of the turbo was larger than it could fit within the engine V, a limitation only exacerbated by further development.
It didn’t take long before the partners shot each other in frustration. McLaren insisted that the body side was excellent and that it would be the frontrunner if it had a competitive power unit.
“The mechanical grip and aerodynamics of the car are not very good. Compared to Red Bull, there is still a big gap,” said Yasuhisa Arai.
“We’ve checked the GPS data. The chassis and aero package need fine-tuning of time, wing angles, ride height, suspension settings, etc.”
It’s easy to imagine the reaction to this statement at McLaren…
At a particularly tense press conference at Monza, Yasuhisa Arai was asked if he would apologize to McLaren’s two world champion drivers for the lack of a competitive F1 engine…
There was a general feeling at McLaren that Yasuhisa Arai had no sense of urgency to improve his performance. Yasuhisa Arai, on the other hand, knew that next year’s engine was ready and he could not make any major changes. This factual communication angered McLaren.
There was definitely a communication and cultural gap between McLaren and Honda F1, with little sense of partnership at any stage.
Years later, Honda F1 was delighted with how open the small Toro Rosso team was about how the engine worked. And Honda responded by giving key members a look into the depths of the Sakura research project, a place no one at McLaren has ever set foot in.
McLaren F1 team principal Eric Boullier showed little anger during a press conference in Monza.
“The McLaren brand is not yet damaged,” said Boullier.
“But if we end up here again next year, it would be a direct loss of revenue as the business is driven by sport.”
Honda F1 may have retorted that McLaren’s revenues were greatly increased by the budget and free engines supplied. Neither would be in this position if McLaren hadn’t insisted on tighter timeframes and size requirements.
The situation has improved, but not enough. Failure in this relationship was already doomed.
Category: F1 / honda f1 / mclaren