Red Bull crushed the 2023 season by winning 21 out of 22 grands prix, with its early dominance allowing the team to hold off on producing many in-season car upgrades.
Instead, the team focused most of its resources on 2024, producing a car that looks substantially different despite its predecessor's successes.
Its decision to go for an aggressive evolution for the RB20 - instead of playing it safe - paid off, with Verstappen winning four out of the first five races of the year, and team-mate Sergio Perez also finding more confidence and competitiveness in the new car.
The Milton Keynes squad's drastic re-design also involved a lot of installation changes for its Honda power unit.
Speaking exclusively to Motorsport.com/Autosport, Honda Racing Corporation president Koji Watanabe said the engine manufacturer was taken aback by all the changes that were made.
"For this year’s Red Bull car, we were very surprised to see that they changed so much for the RB20," Watanabe said.
"Last year we won 21 out of the 22 races together, but they still changed the concept. It is unbelievable!
"They made a lot of requests to adapt our engine to the new concept for the RB20. After we saw the RB20 in real life we were so surprised by all the changes that they made."
In addition to adapting its mounting points to the new chassis, Honda also continued efforts to make its power unit more reliable, which Watanabe explained gave Red Bull more design freedom to place its cooling solutions.
"Of course, we cannot increase the power [under the engine freeze], but we can adapt the engine to the new machine," Watanabe said.
"Apart from that, we can also improve the reliability of the engine. That is what we have done over the past winter.
"This has given Red Bull more freedom for their design and for their aerodynamic concept. That is why they could change the position of the oil coolers, radiators, etcetera.
"Sometimes last year we had a risk to damage the power unit that did not become big trouble in the end, but we always need to minimise the risk.
"That is why we have made our best effort to improve the reliability of the engine even further for this year."
