Sebastian Vettel thinks his 'new' chassis helped him to pull out of his 2014 crisis.
Until Barcelona, the reigning quadruple world champion has struggled at the wheel of his original RB10 car, affectionately nicknamed 'Suzie' by the German.
Asked by Germany's Auto Motor und Sport if he thinks the chassis change was key, Vettel agreed: "I do think it made a difference.
"At least the question mark went away," he added, referring to the uncertain handling of the car he experienced in 2014 until Barcelona.
"As for the pace, it was reasonable," said Vettel.
In Spain, the team benefitted from a new blend of fuel supplied by Total.
"In the car itself you don't feel more power," said Vettel, "but we were not as vulnerable on the straight as usual, so I do think it gave us a bit."
But for the moment, he acknowledged that Mercedes is a long way ahead.
"They have a phenomenal engine, two very good drivers, a very good car, and a very good team, they're doing a good job so it would be wrong to complain and moan about how dominant they are.
"They worked better than everyone else in the winter and deserve to be in that position," Vettel added.
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