Honda reveals development secrets of 2021 F1 engine

Honda has given an unusually detailed insight into the development of its 2021 Formula 1 power unit, which scored its first victory in the hands of Max Verstappen at Imola.

Honda reveals development secrets of 2021 F1 engine

Honda's 2021 engine, the so-called RA621H, is viewed by many in the F1 paddock as the strongest PU in the current field, with Pierre Gasly’s qualifying form for AlphaTauri backing up the pace of Red Bull Racing.

A major package of changes that was in the system had originally been postponed to 2022, but following the Japanese company’s decision to end its official involvement in the sport early it was decided to fast track the new project for this year after all.

That represented a huge commitment, as the call was made quite late last season.

“The original plan was to implement this new structure PU this year in 2021,” said head of power unit development Yasuaki Asaki.

“But then for a variety of reasons, it was decided not to proceed with a brand new PU. However, the thinking on this really changed when Honda announced that we would be leaving the sport.

“I went to President Hachigo, and said to him that we would really like to implement this new structure PU for our last year in the sport. And he kindly accepted that request.”

Read Also:

Asaki stressed that the changes to the layout of the new PU were so significant that a huge amount of work was required.

“That was never going to be an easy task, given the scope of the changes being made to the power unit’s architecture,” he said.

“First of all we've changed the camshaft layout to be much more compact, and also brought its position lower down so it's closer to the ground.

“The main point of what we've changed was to improve combustion efficiency. In order to do so we had to change the valve angle, and in order to do that we had to change the camshaft.

"We've also had to make the head cover lower and more compact, which means that the way that air flows over it has become a lot better, and we've also lowered the centre of gravity of the ICE.

"Another thing we changed is the bore pitch, by reducing the distance between one bore and the next, we've made the engine itself shorter, smaller.

“In the old engine straddling the transmission we also had a bank offset whereby the left bank was slightly offset from the right bank. So what we've done is reverse this offset on the new engine so that the right bank is forward, and the left bank is back.”

Engine cylinders head covers

Engine cylinders head covers

Photo by: Honda

Asaki said that Honda had to address all the key parameters in order to stay competitive with its main rivals.

“Another point that we've had to think about is the fact that combustion efficiency has got better. And the camshaft output has got better. Due to the rules of physics the amount of energy that can be stored has changed, and it meant that the amount of exhaust energy has decreased.

“So compared to the recovery that we were getting last year, what we're having to do is increase the amount of crankshaft output, and at the same time ensure that there's a good level of exhaust output, exhaust temperature as well.

“So we've had a number of different development objectives, and we believe we have met them.”

Input from Red Bull Technology helped to ensure that nothing was left to chance.

“I believe that we were able to implement everything that we have to in order to compete with Mercedes,” said Asaki.

“We had a lot of cooperation from Red Bull, making sure that we could get the most from this new compact engine.

“This is the first time that we’ve gone as far as changing the structure of the PU itself.

“But I think the biggest challenge that we’ve had up to this point was back in the McLaren days, when we made big changes to the MGU-H, we changed the positioning of the compressor and turbine in relation to the V bank.”

Regarding the effort required from his team and the wider Honda company Asaki added: “I had acknowledged in some ways that it was an incredibly challenging target.

“But I think our engineers have had both the understanding that yes, we’ve only got a year left, but also we’ve got a full year left and we have to do something with that time, and they’ve worked hard during the time that we have had.”

shares
comments

Related video

The master manager who juggled Prost and Senna simultaneously

Previous article

The master manager who juggled Prost and Senna simultaneously

Next article

The lessons F1 learned from Berger's fiery Imola crash

The lessons F1 learned from Berger's fiery Imola crash
Load comments
The IndyCar feature that Paul Ricard desperately needs in F1 Prime

The IndyCar feature that Paul Ricard desperately needs in F1

The French Grand Prix offered a surprisingly interesting spectacle, despite the headache-inducing nature of the circuit. But IndyCar's Road America race offered far more in terms of action - and the increased jeopardy at the Elkhart Lake venue might be something Paul Ricard needs in future...

French Grand Prix driver ratings Prime

French Grand Prix driver ratings

The French GP was a weekend decided by tiny margins both at the front of the field, as Red Bull inflicted a comeback defeat on Mercedes, and in the battle for the minor points places. That's reflected in our driver ratings, where several drivers came close to a maximum score

Formula 1
Jun 21, 2021
How Red Bull took French GP "payback" on a day of Mercedes mistakes Prime

How Red Bull took French GP "payback" on a day of Mercedes mistakes

The French GP has been a stronghold for Mercedes since Paul Ricard's return to the calendar in 2018. But that all changed on Sunday, as a clever two-stop strategy guided Red Bull's Max Verstappen to make a race-winning pass on the penultimate lap - for once leaving Mercedes to experience the pain of late defeat it has so often inflicted on Red Bull

Formula 1
Jun 21, 2021
The Mercedes lap that puts F1 victory fight back on a knife-edge Prime

The Mercedes lap that puts F1 victory fight back on a knife-edge

Red Bull led the way after the first two practice sessions for the 2021 French Grand Prix, but only just ahead of Mercedes. There was all the usual practice skulduggery complicating the performance picture, but one aspect seen at the world champion squad gave it a ‘surprise’ lift, as it looks to leave its street-circuit struggles firmly in the past.

Formula 1
Jun 19, 2021
How Ferrari got its F1 recovery plan working Prime

How Ferrari got its F1 recovery plan working

After its worst campaign in 40 years, the famous Italian team had to bounce back in 2021 – and it appears to be delivering. Although it concedes the pole positions in Monaco and Baku paint a somewhat misleading picture of its competitiveness, the team is heading into the 2022 rules revamp on much stronger footing to go for wins again

Formula 1
Jun 18, 2021
The joy that exposes F1’s key weakness Prime

The joy that exposes F1’s key weakness

Long-awaited wins for ex-Formula 1 drivers Marcus Ericsson and Kevin Magnussen in IndyCar and IMSA last weekend gave F1 a reminder of what it is missing. But with the new rules aimed at levelling the playing field, there’s renewed optimism that more drivers can have a rewarding result when their day of days comes

Formula 1
Jun 17, 2021
The F1 figures Red Bull and Mercedes can't afford to see again Prime

The F1 figures Red Bull and Mercedes can't afford to see again

OPINION: An interloper squad got amongst the title contenders during Formula 1’s street-circuit mini-break, where Red Bull left with the points lead in both championships. But, as the campaign heads back to purpose-built venues once again, how the drivers of the two top teams compare in one crucial area will be a major factor in deciding which squad stays in or retakes the top spot

Formula 1
Jun 16, 2021
Why Alfa's boss is up to the task of securing a stronger F1 future Prime

Why Alfa's boss is up to the task of securing a stronger F1 future

Two tenth places in recent races have lifted Alfa Romeo to the head of Formula 1's 'Class C' battle in 2021, but longer-term the Swiss-based squad has far loftier ambitions. With the new 2022 rules set to level out the playing field, team boss Frederic Vasseur has good reason to be optimistic, as he explained to Motorsport.com in an exclusive interview

Formula 1
Jun 15, 2021