F1 rivals left asking, "Why is the Red Bull so fast?"

The pace of the Red Bull cars this weekend has really shocked its rivals, all of whom are heading back to the drawing board after the updates their brought here seem to have taken them further away rather than closer to the pace setters.

Mark Webber took pole today with a lap which was 9/10ths of a second faster than the McLaren, a second faster than the Ferrari and 1.3 secs faster than the Mercedes.

"I came here thinking that we could really put on a challenge now and it's not gone that way. We really need to look into it, in terms of our competitors we are not where we want to be and we have made a small step back, " said Nico Rosberg, currently second in the world championship.

"One team is untouchable while the other top three teams are very close," said Ferrari boss Stefano Domenicali.

Mercedes boss Ross Brawn broke down exactly how the Red Bull is setting such unreachable lap times in qualifying trim,

"We can see where they are quick," he said."Turn 9, the high speed corner, they are quite exceptional through. It's high speed corners and this is a track where there are lots of high speed corners. That's their strength. It was also their strength last year but they had a weakness in slow corners last year. This year they are good in slow corners and had retained their ability in high speed corners."

What is particularly striking is that they are only 20th and 21st through the speed trap 9km/h slower than the Ferrari, which is a lot to give away.

World Championship leader Jenson Button said," They have very good traction and they can carry speed through the corners because they have a stable rear end. On corner exit they are very strong. I'm a little bit surprised at how quick they are. They are in a very good position."

Everybody has come to Barcelona with improvements to their cars. Red Bull has been secretive about the new parts it has on its car, except to admit that the mechanics have had hardly any sleep over the last two nights as they fitted the new parts. There are obvious updates on the front wing and detail on the diffuser, there is also some improvement to the floor. Clearly the downforce creating elements of the rear of the car, the diffuser and the rear wing are giving the car a very stable rear end and this is balanced out by a large and sophisticated front wing.

However McLaren believe that the Red Bull is not so far ahead in race trim as it is harder on its tyres than the other top teams. With the top ten cars starting the race on the soft tyres on which they qualified, the long fast corners will ask a lot of questions of the front left tyre and it will be interesting to see how the Red Bull handles the opening stint on full fuel tanks.

From what we saw in Friday practice, however, the Red Bull looked pretty good on the long runs. Webber did a 19 lap run which was pretty consistent in the 1m 24s and 1m25s, tailing off in the final three laps into the 1m 26s. At the same time Schumacher did a 14 lap run which started in the 1m25s and slipped into the 1m26s after six laps.

"It´s a surprise for all the others but also for us," said Vettel. "It´s a dangerous thing as well because we need to keep pushing and also to confirm it tomorrow (in the race).