https://www.autosport.com/f1/news/ho...ngine/6417548/
Honda reveals development secrets of 2021 F1 engine
By:
Adam Cooper
Apr 23, 2021, 7:27 AM
Honda has given a 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 RA621H, is viewed by many in the F1 paddock as the strongest PU on the grid, with Pierre Gasly’s qualifying form for AlphaTauri backing up the pace advantage of Red Bull Racing.
Verstappen took Red Bull and Honda's first victory of the season in last weekend's Emilia Romagna Grand Prix, and the RB16B has proved to be the quickest car on the grid so far this year.
A major package of changes to the Honda PU had originally been postponed to 2022, but following the Japanese company’s decision to end its official involvement in F1 at the end of 2021 it was decided to fast track the new project for this year.
“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 [Takahiro] 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.”
Asaki stressed that the changes to the layout of the new PU were so significant that a huge amount of work was required, as well as input from Red Bull Technology.
“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.”
Red Bull Racing RB16B
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," he said.
"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.”