Red Bull will try out a new rear aerodynamic part at this weekend's Turkish Grand Prix to help maintain its lead over closest rivals McLaren and Ferrari. Overall Formula One leader Mark Webber said Thursday the Austrians will debut their F-duct wing - a device that produces greater speed on straights - in Friday practice. Webber, who shares 78 points with Sebastian Vettel but leads with two victories to his teammate's one, believes McLaren will be Red Bull's biggest worry at the “Otodrom.” “Lewis (Hamilton) was our closest competitor at Barcelona, so I think McLaren might be the guys that challenge here,” the Australian driver said. “We're also mindful of Ferrari and Mercedes. We're definitely not taking anything for granted.” The Williams team, meanwhile, arrived at the Istanbul Park circuit Thursday to prepare its ‘old' cars after losing a race against time to build updated versions following a crash-marred showing at the Monaco Grand Prix. Both veteran Brazilian Rubens Barrichello and German rookie Nico Hulkenberg had crashes in Monte Carlo which left both of their cars needing major repairs and new parts. Technical boss Sam Michael said: “Nearly all of the items that needed replacing after Monaco have been done - apart from the front wings, which require more time. “As a result of that we have had to revert back to a previous specification of the car for this race in Turkey.” Michael tried to put an upbeat spin on this setback by adding that they expected to have all-new updated cars ready for the Canadian Grand Prix in Montreal on June 13. And he added that they hoped to have a performance boost from using upgraded Cosworth engines this weekend together with new brake ducts and other minor mechanical changes. Barrichello's car was damaged because of a loose manhole cover which prompted the third Safety Car period in the Monaco race after Hulkenberg crashed at high speed in the tunnel on the opening lap. Barrichello was, at least, relieved to learn of the cause for his accident on a bleak weekend for the team that is struggling to revive old glories.
