McLaren-Mercedes is currently enjoying an advantage of some 25bhp over any of its Formula 1 rivals, it has been claimed - equivalent to four tenths of a second per lap.

There is little question that the Woking-based outfit is the in-form team in the top flight at the moment, having triumphed in the last three grands prix in succession courtesy of Lewis Hamilton and Heikki Kovalainen.

Reports have suggested that behind such superiority are design improvements - including the Honda and BMW-esque nose wings that made their maiden appearance in Hungary three weeks ago - mated to the unmatched power of Mercedes-Benz's 2.4-litre, V8 powerplant.

"If those numbers are right, then an advantage of 25 horsepower with the same air resistance brings a benefit of four tenths [per lap]," BMW-Sauber technical director Willy Rampf told German magazine Auto Motor und Sport.

The Stuttgart manufacturer's motorsport vice-president Norbert Haug, meanwhile, has anticipated a greater number of safety car periods than usual during this weekend's European Grand Prix in Valencia, the first F1 race to be held around the streets of the Spanish city.

Safety cars are far from a rarity during street races, and Valencia's harbour-side layout features a higher top-speed than most concrete barrier-lined street circuits. Haug urged that - with the track being new to everyone - drivers would be wise to ease themselves into the weekend gently.

"They need to keep the car on the track and collect as much data as possible," the German told Auto Motor und Sport. "Of course, we must think about the safety car for our tactics more than we usually do too."

It has also been revealed that - unlike the other new addition to the 2008 calendar in Singapore - the race in Valencia is not a sell-out as had been predicted. German news agency SID states that not all of the 112,000 tickets for Sunday have yet been snapped up.