Felipe MassaMcLaren has admitted that it has no idea how to replicate the front wing setup currently being used by Red Bull Racing and Ferrari.

The legality of the front wings – approved by the FIA prior to the German Grand Prix – had been questioned by rival teams after close scrutiny revealed the wings, and endplates, seemingly flex up to 25mm lower to the ground at high speed, producing more downforce as a result.

McLaren's engineering director Paddy Lowe conceded that despite reviewing the flexi-wing design repeatedly, he is struggling to emulate it.

"I've seen a lot of pictures on that situation," he said. "We believe, and we're not alone, that two cars – Ferrari and Red Bull – have wings existing at a much lower position than we're able to deliver. It is a phenomenon we're seeing. It may be entirely legitimate, it may not be. We don't understand it."

McLaren is convinced, however, that the anomaly cannot be explained by simple setup adjustments.

"It is a difference to a reasonably large degree," says Lowe, "so it's difficult to explain by relatively subtle effects like fuel weight, tire pressure, or high-speed setup. These things affect a car to a relatively small degree – much smaller than the degree we've seen in pictures.

"At the minute, we are working really hard to understand it, and if it is worth performance to us, to deliver that."

Lowe's comments come two days after McLaren team principal Martin Whitmarsh said that he too was struggling to explain the flexi-wing design.