Carlos Sainz reckons in Renault’s C-spec engine they have the baseline for a power unit that will can be “at the level of Mercedes and Ferrari.”
Although initially only Ricciardo run the update, Red Bull decided to swap Verstappen to the C-spec after seeing significant gains.
Renault, though, have yet to use it themselves.
And while Sainz says that’s disappointing as they could do with the added boost, he hopes when he moves to McLaren next season that Renault update will put the Woking team’s power unit on a par with “Mercedes and Ferrari”.
“The C-spec is the baseline of next year’s engine,” the Spaniard told Autosport.
“It looks to be working well in the Red Bull, and they look pretty pleased with that.
“That’s a good step. It’s a shame that we didn’t have it this year because it would make our life a lot easier against the Haas and against the Force Indias.
“I have faith that Renault is going to finally make an engine at the level of Mercedes and Ferrari.
“Together with that partnership with McLaren I hope to have a better year than this one.”
Looking ahead to his final seven races with the Renault works team, Sainz revealed he won’t be swapping to the C-spec engine so any gains need to come from the chassis.
“We won’t have many more developments on the engine side, we need to focus on the car,” said Sainz.
“It’s good that they [Red Bull] run it because the engine guys can learn from that and put the findings into next year’s development.”
He added: “I know the chassis department and the aero department are pushing flat out.
“We’re obviously stuck with this type of engine until the end of the year.
“If the aero parts work and we make it to the finish in P4, everyone will be proud, everyone will be happy.”