Toro Rosso team principal Franz Tost says Renault and Honda will get "much closer" to Ferrari and Mercedes in 2016.
Mercedes has had the dominant power unit since the introduction of new regulations at the start of 2014, but Ferrari made a big step forward to close the gap this season. With Renault and Honda struggling, Tost says he expects to see both making clear progress next year otherwise the FIA will have to take action.
“I expect them to be much closer next year,” Tost told the official Formula One website. “I am convinced that they have the resource and know-how to close the gap.
“If not then the FIA has to look into the [engine development] token story so that everybody who is behind gets extra development freedom until we have parity. But as I just said, I am sure that those behind will catch up, at the latest by 2017.”
However, while Tost has confidence in current power unit supplier Renault, he says it is most likely Toro Rosso will run with Ferrari power next season.
“If you take into consideration that we have paid a lot of money [to Renault] and didn’t see progress as we had expected, then there must be the question of why not go back to Ferrari - a partner we know and who also makes sense logistically."
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