McLaren and Ferrari completed their second day of running at the new Autodromo Internacional do Algarve in Portimao, Portugal, with McLaren test driver Pedro de la Rosa going quickest.
De la Rosa took over from Gary Paffett and spent the day developing the KERS-fitted McLaren MP4-23K.
The Spaniard posted the fastest time of the day with a 1:30.080, despite having to grapple with low grip in the early part of the day as a result of the low-speed circuit configuration, green track surface and cold December weather.
Ferrari test drivers Mark Gene and Luca Badoer took over from Felipe Massa and lapped second and third quickest respectively on a 1:31.320 and 1:31.076.
Both Gene and Badoer focussed on developing the setup of the 09′ hybrid F2008.