Jul.4 (GMM) Nervous eyes will be on Red Bull this weekend, after Sebastian Vettel stunned his rivals with the RB8's pace last time out at Valencia.
Team boss Christian Horner had described the car's improvements as "small", but Vettel was suddenly a second per lap faster than any rival on the Spanish street circuit, recalling his utter dominance of the 2011 season.
"It was very impressive and so all the teams will be looking closely at what they do at Silverstone," Mercedes' Ross Brawn is quoted by Auto Motor und Sport.
Horner, however, is keeping expectations down.
"So many cars have looked fast at different events," he told the Mirror.
"For sure we made a step forward at Valencia, but the circuit challenge of Silverstone is totally different.
"It has high speed corners and quick changes of direction and, probably, a lot cooler temperatures with the likelihood of rain as well."
Sam Michael, key rival McLaren's sporting director, agrees with Horner that it is too soon to predict more Red Bull dominance from now on.
"It's clear Red Bull have taken a step forward, although I don't think it's as big as the pace that Sebastian Vettel showed (at Valencia)," he told reporters during a team sponsor teleconference on Wednesday.
Australian Michael said he thinks Red Bull's Valencia dominance was less to do with the car updates, and more to do with simply getting the finicky tyres to work perfectly.
"A second a lap is quite a lot when you've changed fairly secondary parts on the top surface of the floor," he said.
"I'd be pretty surprised if they maintained a second a lap gap to the rest of the field."