Whincup quickest in Friday practice at Winton Motor Raceway

TeamVodafone's Jamie Whincup has fired a warning shot to his championship rivals in this afternoon's final practice at Winton Motor Raceway.

The series leader, who could mathematically seal the 2012 title this weekend, set a benchmark 1m23.7726s lap time on just his second flying lap and was never headed in the 30-minute session.

Whincup remained the only driver to break under the 1m24s bracket.

"We split up our practice runs, half of it was testing for the race and the other half was testing for qualifying," said Whincup.

"We haven't qualified well here in the past so that's a focus of ours. Obviously we'll make some more tweaks to make it go quicker but it's certainly in the window at this stage."

"It's not important to wrap up the championship this weekend, we're going to go out there and race as hard as we possibly can. I'm certainly not going to conserve."

Tony D'Alberto was second, ahead of Fujitsu Racing's Michael Caruso.

"We haven't finished a lot of races lately so I've got about a hundred green sets of softs in my bank!" explained D'Alberto.

"I wasn't that wrapped with the car today, the track was hot and the car wasn't behaving how I liked but hey, if we can make it into the top three times at the end of the day it hasn't been too bad."

Championship contender Mark Winterbottom was fourth and FPR teammate Will Davison rounded out the top five.

Team BOC's Jason Bright was sixth, with James Moffat (Team Norton DJR), Lee Holdsworth (IRWIN Racing), David Reynolds (Bottle-O Racing) and Fabian Coulthard (Lockwood Racing) filling the top ten positions.

Whincup's teammate Craig Lowndes could only manage the 20th fastest time. Just one second covered first to 22nd (Steve Johnson).

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