Spa-Francorchamps: New stress tests, introduced at the Belgian Grand Prix after concern about the Ferrari and Red Bull front wings, have had an immediate effect according to rival Formula One teams.
Although Red Bull secured pole position for the 12th time in 13 races, McLaren boss Martin Whitmarsh and Mercedes team principal Ross Brawn both agreed that there was a visible difference.
"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," Whitmarsh told reporters after qualifying on Saturday.
"I think we could all see it, and the evidence that was collected yesterday showed that in regards to stiffness and position the front wing endplates of those cars appear to be in a different domain (position)."
Formula One`s governing body has imposed tougher tests on front wings after some teams sought a clarification of photographic evidence that suggested the wings were illegally flexing lower at speed.
A further tightening of the rules is expected for the Italian Grand Prix at Monza in two weeks` time.
"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," said Brawn.
"I don`t know what has happened but it looks visually to me to be different."
McLaren`s Lewis Hamilton qualified on the front row at Spa alongside Red Bull`s championship leader Mark Webber, whose fastest lap in the third and final part of the session was only 0.085 quicker than Hamilton`s best effort.
In Hungary, Red Bull`s Sebastian Vettel was 1.7 seconds faster than Hamilton in qualifying.
Red Bull team boss Christian Horner said this week that the front wings on his cars in Belgium were the same as those used in Budapest.
"We`ve been questioned so many times this year -- whether it be ride-height systems, whether it be suspension, whether it be blown diffusers," he added.
"It has been the front wing and now it is the floors, so our guys take it as a compliment that so much of the car has attracted so much attention."