Jenson Button has confirmed rumours that Honda are set to completely redesign their power unit for the 2017 season, as it comes to the realisation that it can't match the performance of the leading Mercedes unit.
It's believed Honda are aware that without changing large swathes of the internal combustion and turbo system, they won't be able to match the horsepower output of their rival engines. However due to the limited development tokens available to them, the redesigned power unit won't be introduced until 2017.
A recent rule change, which will see tokens scrapped after this season, means Honda – or any engine manufacturer – can essentially introduce an entirely new design ahead of the homologation deadline in February.
Speaking to NBC, Button confirmed that design limitations were restricting the performance McLaren and Honda can extract from the power unit.
"I think with the way the engine is, yes, I think it’s difficult to extract the power that we feel that we need. And that’s not me saying that, that’s Honda," said the Briton.
"And that’s why the makeover for next year [is needed]. They’ve made some big steps this year with the engine but I think to make the big step to the top teams is very difficult [without a redesign]."
Button believes McLaren are now ahead of the midfield in terms of chassis and aerodynamics.
"Compared to the middle teams we’re stronger, I should think, in terms of how the car feels. But we want to compare ourselves to Ferrari and the Mercedes. There’s areas where we need to improve. We’re working on it."