Grosjean urging Haas to change brake supplier

Haas F1 Team is still struggling to resolve a chronic brake problem which has lingered since last year, with Romain Grosjean hoping a supplier change is in the works.

The issue appears to involve a lack of consistency of Brembo's disc and pad ensemble.

Haas is investigating the possibility of testing Carbone Industrie's product sometime in the neat future to conduct a proper compare, although the team briefly experimented with Carbone in Brazil last year.

For Grosjean, who ditched his VF-17 in the gravel trap at Turn 5 this morning on the ultimate day of pre-season testing, a supplier change can't happen soon enough.

"I'm not going into detail, but I don't like it," the Frenchman told Motorsport.com.

"I can't wait to get back to something different. Now, when will it arrive? I don't know."

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Brake issues notwithstanding, Grosjean is pleased with the progress so far of the US outfit's VF-17 car, although the team is still trying to iron out an understeer characteristic generated by the new chassis.

"Yeah, we are struggling a bit with understeer," he said.

"We need to understand why. We've been trying a lot of different set-ups and a lot of different things, assessing what tools do what.

"You don't need a perfect set-up here in winter testing, but we want to be able to know, if we change the rear suspension geometry or the front stiffness, what does it do, and so on."

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