Jenson Button: Toyota will win Silverstone WEC race by four laps

Both 2018/19 WEC races so far have proved Toyota walkovers - it finished two laps up on the third-placed Rebellion at Spa before winning the Le Mans 24 Hours by a crushing margin of 12 laps.

The championship made several Equivalence of Technology tweaks ahead of the Silverstone race to try to close the gap between Toyota and the privateers.

But the two TS050 Hybrids still proved two seconds quicker than the best non-hybrid, the #11 SMP Racing BR Engineering BR1 shared by ex-Formula 1 drivers Button and Vitaly Petrov, in qualifying at Silverstone.

Button predicted that Toyota "will be four laps ahead" by the end of Sunday's six-hour race.

"If it's a clear track and there's no traffic, we're probably two seconds a lap slower," he said.

"But we can't overtake like they can because we don't have the boost.

"In traffic, we're four seconds a lap slower. So it's tricky.

"I guess we'll be four laps down. We're not racing them, they're racing each other.

"We've got the Rebellions, which is fun, and I don't know what the DragonSpeed [customer BR1] will be like in the race either. So that's going to be a good little race, I think."

Asked about whether the EoT adjustments had made any difference, Button said balancing the hybrid-powered Toyotas with their privateer counterparts would be impossible.

"They are never going to be as quick as the hybrid, factory team," the 2009 F1 champion conceded.

"They're spending over a hundred million [dollars], and we're minuscule compared to what they would be spending on development and what have you.

"There's no comparison. Then they've also got four-wheel drive; the tyres that we use are built for a Toyota.

"So we overheat the rears and we never get the fronts working because the fronts are built to be driven by power."

Mike Conway, who along with team-mate Jose Maria Lopez put the #7 Toyota on pole at Silverstone, said he expected the non-hybrid cars to be closer given the EoT change.

"We thought they would be quick, from what we saw on simulations," Conway told Autosport. "We thought they would be a bit closer.

"If they could do the same lap time as us in the race, that would be great. We'd like to see them be that close.

"We still have the advantage of managing our boost, getting around traffic, that's where our advantage is.

"We want them closer, for sure. But looking at the longer runs yesterday, we still have a decent advantage."

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