Front wings not flexing in Belgium – rivals
New FIA tests to ensure the rules compliance of the front wings and floors are taking effect this weekend and at Monza in two weeks, after Red Bull and Ferrari's cars came under the spotlight.
McLaren team boss Martin Whitmarsh told reporters at Spa-Francorchamps that the offending wings are not flexing as much in Belgium.
"I wasn't that confident that it (the problem) would be nailed but I have to say … the wings were of a different stiffness and positional domain than they had been in previous races," he is quoted by Reuters.
Mercedes' Ross Brawn added: "I think all of us can see that what was visible in the last couple of races doesn't seem to be the case here.
"I don't know what has happened but it looks visually to me to be different," said the Briton.
Red Bull's Mark Webber on Saturday secured pole for the Belgian grand prix, less than one tenth ahead of McLaren's Lewis Hamilton.
Both Red Bull and Ferrari have said they are using identical wing designs this weekend to the ones raced in Hungary before the summer break.