McLaren racing director Eric Boullier says his team is currently split equally between work on its 2016 and 2017 F1 car.

New regulations are set to be introduced in 2017 which will lower lap times by up to five seconds per lap compared to Barcelona 2015, with the set of rules which have been accepted being known as the McLaren proposal. While the FIA is yet to finalise all aspects of the regulations - with cockpit protection still being tested - Boullier says around half of his team is now working on next year's car.

"Well obviously we had to wait for the final decision of the regulations so there was obviously a push-back, when you switch your resources," Boullier said. "So today I could say we are 50/50 looking at and still working on the current car."

Paddy Lowe confirms Mercedes is similarly switching focus but says there is a limit to how many people can work on 2017 at this stage.

"It’s always a gradual migration but with such a big rule change, we’re inevitably migrating earlier than normal," Lowe said. "But having said that, in the early phase of a project you can’t put hundreds of people on a programme where you haven’t fixed the major parameters, so its inevitably a gradual process."

Despite the late confirmation of the final regulations, Toro Rosso technical director James Key says the previous discussions on them have allowed teams to still start work at a reasonable time.

"I think, to be honest, the birth of the ’17 regs, if you like, was always a little bit long-winded," Key said. "And so we had a pretty good idea what the chassis direction was likely to be from a tyre and suspension viewpoint, at least dimensionally but we took a little while to try to define the aero regs and the bodywork regs.

"So, in that respect, everyone’s had a start-point, which is maybe a little later than you’d want for a very fresh set of regulations. But there was still plenty you could do on the principals of a ’17 car beforehand, so we’ve been working on it for several months, as I’m sure everyone else here has.

"The split’s difficult to define at the moment because it depends of which department… engineering discipline, let’s say, you look at. But certainly on the aero side there’s a pretty massive impact from all of this, so there’s a big emphasis from us on the aero side. The same with simulation. The design office is yet to really pick up the big bits but certainly by after the August break they’ll be pretty much 100 per cent on next year’s car."

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