Max Verstappen believes that Red Bull is running significantly behind rival teams when it comes to engine upgrades in 2018.
The Dutch driver was speaking in Hungary, where his most recent Grand Prix ended just five laps in to the race because of an issue with the car's MGU-K. It's the latest in a number of engine-related issues suffered by the RB14 this season.
Verstappen was frustrated by this latest failure, and said that the team had to do better in future. He pointed to the speed that their rivals - including the works Renault team - were able to design and implement upgrades.
"If there are new parts, they will of course go to the factory team first," he said. "Which is also logical, but it’s a pity for us.
“You just know that at Ferrari and Mercedes these are immediately introduced," he added. "Then they might have advantage of that for one or two races, before the rest takes a step.
"We are always two races behind," he concluded.
The situation is exacerbated by the fact that Red Bull has opted for a different oil and lubricant supplier from Renault, which supplies its TAG Heuer branded power units.
Red Bull uses ExxonMobil products, while Renault and the other customer team McLaren both use BP Castrol. The difference means there is extra work in testing and optimising upgrades.
But Verstappen felt this was not an important part of the equation in terms of why Red Bull weren't getting the latest upgrades.
"Difficult to say. For example, with the petrol, we could have had this [in Germany]. But we only get it now, because they were not sure of reliability," he sighed. "It’s these kinds of things.
“Especially now they have their own factory team, you're always a little behind on things."
It's why Verstappen is happy with Red Bull's decision to end its 12-year association with Renault and switch to Honda power units in 2019.
But in the meantime it seems that the team's campaign for the remainder of this year has inevitably been affected.
“Now that it’s certain that you are making the switch to Honda, that will not work in your favour, let’s put it like that," he admitted. "But that's how these things work, and we know that, so you just need to accept it.
“I hope we will continue to develop the car well,” he added. “The engine is a difficult story.
“We are better than them [Mercedes and Ferrari] in terms of car," he insisted. "So car-wise they are the ones who need to catch up."
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