Mark Webber, Red Bull, Singapore GPMark Webber says the new flexing-tests have not affected Red Bull's performance at all after the team dominated Singapore GP practice.

At the previous race at Monza, the FIA introduced a series of new rules and tests amid suspicions from rivals that Red Bull and Ferrari were exploiting the regulations – through either flexible bodywork or a bending floor. All teams passed the tests at Monza.

Red Bull endured its hardest race of the season in Italy, but the team always admitted the nature of the track did not suit its car. Things seemed to return to normal on Friday, with the team showing incredible speed in practice.

Webber was quickest in the morning session, while teammate Sebastian Vettel finished on top in the afternoon, a full second clear of the first non-Red Bull car. The Australian insisted the new tests have made no difference to his team.

"We're struggling with the new rules!" joked Webber after practice. "We knew nothing would change in that sense. Ferrari still looks quick, so we weren't coming here expecting to be slower than we were in Budapest.

"Other people have their own ideas how they are going to improve their car, but we always try to improve our car. Tomorrow, McLaren could be on pole, so let's see where we are. But we know where we are, we know where we are going and we know we have clever guys doing the right thing at the right time.

"Our car has never failed a test ever this year. The tests keep changing, but we keep doing our best."

Webber admitted he wasn't too happy with his performance over a single lap, but the championship leader was far from worried.

"I wasn't mega-happy with my short-run performance but I wasn't cruising; but it is Friday, and there are no points. Building up for tomorrow.

Vettel was encouraged by his pace today, but downplayed its significance.

"I am happier than everyone else. We have to see. It is Friday. It doesn't mean a lot – all that matters is Saturday and Sunday. But it's better to be on top than be behind, and to be on top by quite a bit is a nice thing. The weather is always good for a surprise. We had a good pace. But we will see."

He added: "I think the most important thing is if you have a clean Friday. We had no problems with the car, which is the main thing, so all the rest is in the stars."