Honda have revealed the work behind their 2021 power unit which has played a significant role in Red Bull's and AlphaTauri's impressive performance this season.
Max Verstappen won last weekend's Emilia Romagna GP and came close to winning the season-opener in Bahrain. Honda brought forward a new power unit for this year as they are set to leave the sport at the end of the season.
They have explained the changes to their power unit which is now a match for Mercedes.
"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," Honda's head of power unit development, Yasuaki Asaki, told the press.
"They’ve worked hard during the time that we have had. 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.
“We’ve also had to change the valve angle. 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."
'Derates', when the car stops accelerating at the end of the straight, have been a common problem for Honda whilst their engine has been less efficient than Mercedes in the past too. However, there have been no such issues so far in 2021 which has allowed the drivers to push hard throughout the race.
"We've had to think about is the fact that combustion efficiency has go better and the camshaft output has got better," said Asaki. "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.
"We've had a number of different development objectives and we believe we have met them.”
Asaki believes Honda's communication with Red Bull has been pivotal in order for the Milton Keynes-based team to work around the new engine.
He acknowledged the major challenge Honda have faced to get the new power unit ready in time for 2021 and made a comparison to some of the changes that were made during their time with McLaren.
“This is the first time that we’ve gone as far as changing the structure of the PU itself," added Asaki. "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. “I believe that we were able to implement everything that we have to in order to compete with Mercedes."