Red Bull's RB19 has been the class of the field in 2023, propelling Max Verstappen and Sergio Perez to a clean sweep of seven wins in the first seven races of the season.
The car has looked particularly planted in high-speed corners but, despite its downforce prowess, the car has also enjoyed a straight-line speed advantage over the competition, both with and without DRS.
When asked about the main asset of the car, technical director Wache replied: "Efficiency, I would say.
"On different tracks, we are able to produce downforce without massive drag, which I think is the main strength."
Rival teams have suggested that Red Bull is compromising its qualifying pace on Saturday to be stronger in the race, and that it is still racking up poles thanks to the size of the advantage it enjoys over the competition.
But Wache refutes suggestions Red Bull has pace in hand. "Not really. In qualifying, for sure we are pushing," he added.
"During the race, as everybody we are saving or managing the tyres to increase the stint length and to give more choice on strategy, like everybody is doing.
"The success is also depending not on you but also on the others. And the difference is bigger than what we expected."
According to Wache, Red Bull's rivals Aston Martin, Ferrari and Mercedes have been steadily narrowing the gap in qualifying on circuits that suit them, while Red Bull continues to hold a significant advantage in how the RB19 manages the tyres across stints.
"You see that in qualifying for sure they were every time closer in terms of pure performance," he explained.
"In terms of management of pace during the race, we have some advantage. But I'm sure they can unlock [more performance]. And you see some updates coming from our competitors here. For sure it will be closer."
Wache's Aston Martin counterpart Dan Fallows isn't convinced that teams are truly beginning to close the gap to the Milton Keynes squad, after Verstappen put 24 seconds on nearest rival Lewis Hamilton in the Spanish Grand Prix.
"I think that that is a little difficult to say, because of the behaviour of the car," he said. "Obviously, in Monaco we were very close and in Spain less so. In truth, we clearly see that there is a gap to Red Bull. There has been all season.
"But I think what's also really important for us is how nip and tuck it is with Mercedes and Ferrari.
"I think it is particularly great for the fans to see that kind of battle going on for the second place at the moment."
