Feb.14 (GMM) McLaren showed to have taken the aerodynamic 'wheel cover' concept to a new level as testing continued at the Jerez circuit on Thursday.

Heikki Kovalainen's Mercedes-powered MP4-23 featured a new version of carbon fibre covers on the front wheels, and for the first time they include a piece that extends beyond the wheel rim and obscures part of the tyre wall.

Interestingly, at the lunch break, the Finn had set the fastest time of the sixteen runners in action, and gone more than five tenths quicker than Mark Webber's Wednesday best.