Toro Rosso won’t use Renault upgrade - Sainz

Carlos Sainz reveals that Toro Rosso will not use the upgraded power unit Renault has made available for this weekend’s United States Grand Prix, as the team believes “it’s not worth” taking grid penalties.

The French manufacturer has brought a new engine specification to Austin, which should “give improved power and efficiency” according to Renault Sport F1 director of operations Remi Taffin.

The Viry-based constructor was the only supplier yet to introduce an evolution to its power unit, with senior management repeatedly indicating that they would rather have one major development instead of several smaller updates.

According to motorsport.com, Renault spent 11 of its 12 allocated engine tokens to enhance its troublesome 2015-spec power unit, but half of its supplied teams has already turned down the offer.

“We're going to stick for the rest of the year with the old spec,” said Sainz. “Given the values that they've given to get another grid penalty and start last, especially with the last four tracks being similar to this one.

“OK, these are not the best tracks [for us] because they have long straights, but they’re not the worst, so we can be very close to the top 10, top eight in some of them.

“So to start last, I think it's too much, it's not worth it, so we will commit to this year's spec that we have now, that's good enough to finish the year, and we have plenty of them.

“It's an important end of the season now, because we have four races where the tracks should not be bad for us, and we already lost a lot of points in the middle of the season.

“We need four races where we can qualify decently and race hard from the top 10. So I don't want to take more penalties to be honest.”

• Eric Silbermann's United States Grumpy preview

In the wake of Red Bull’s fallout with Renault, junior squad Toro Rosso’s presence in F1 beyond 2015 remains uncertain, though it is reported that the Faenza-based outfit is closing in on a return to the Ferrari fold.

With his future also in the balance, Sainz nonetheless remains confident of a positive outcome for he and his squad.

“From the drivers’, engineers’, and mechanics’ point of view, everyone is quite calm about it. Everything looks a bit more settled down, even though we have not signed a contract yet. I think everything is pointing to the right direction.

“On my side, I don’t really care. I’m completely sure they’ll come to a solution and I really hope so. It’s just a matter of time, hopefully sooner than later, so that we can start working on next year. I think it’ll be pretty soon.

“I really hope we can sign something this week or next week, and then fully focus on the present and not so much on the future.”

Click here for Chris Medland's United Grand Prix preview

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