V8 Supercar title hopeful Mark Winterbottom, who led Friday's open practice at the Falken Tasmania Challenge, is looking for Series leader Jamie Whincup to make a mistake so he can make a bold bid for the Championship.

Winterbottom was delighted with the speed of his car as the drivers faced both dry and wet conditions during the three practice sessions at the tight Symmons Plains circuit near Launceston in Tasmania.

He comes into the penultimate round of the Championship trailing leader Jamie Whincup by 189 points, needing to make up big ground this weekend before the NRMA Grand Finale at Oran Park in Sydney in a fortnight.

Winterbottom believes he can do well in the Tasmanian sprint races but reckons that Whincup, who was out of the top 10 for much of the day before climbing to sixth fastest, may have some battles.

He recalled that Garth Tander came to Symmons Plains with a similar lead last year but left in second placed after a dismal weekend.

"It would be nice if he (Whincup) did that," Winterbottoms aid. "He is quick though and when you stay up the front it tends to be a bit cleaner. But Garth (Tander) had a go at Richo (Steve Richards) last year and broke his steering.

"Who knows what might happen. This track is tight and always gives quite an interesting couple of races. I guess after tomorrow's qualifying we will know who is where but it would be nice if Jamie donated a few points back."

Whincup's Vodafone Ford team-mate Craig Lowndes, second fastest in practice, reckons it will be pit stop strategies that will play the major role tomorrow, where the average lap is under a minute on the 2.4km circuit.

He had a skirmish with Russell Ingall coming around on a hot lap as the Enforcer made his way out of pit lane.

"That's always an issue here especially when it comes time for strategy with pit stops in and out. I am sure every team will be looking pretty closely at that. It's a track where you must have track position so if you can't do it in qualifying they will try to do it through strategy. Therefore the pit stops will be very interesting."

Third placed Tander was third fastest today and pleased with his car as he pushes for a possible defence of his V8 Supercar crown.

"There's a slight possibility it might happen. The good thing is our car was strong out of the box today and I am very pleased."

The drivers had to cope with a sharp shower in the middle of the three practice sessions with some drivers testing out their cars in the wet and others preferring to save themselves.

They will all have to chase Winterbottom who was delighted with the Ford's speed on a track that they dominated last year, finishing in a Blue Oval trifecta.

"It was nice to have the car back to where it has been a couple of races ago. Tomorrow may be quite tricky as it could be dry and it could be wet. That could make for some pretty interesting and exciting racing."

Paul Dumbrell was fourth fastest ahead of Steven Richards, Whincup, James Courtney, Will Davison and Mark Skaife, in his final race at Symmons Plains before retirement.

There is qualifying and race one tomorrow [Saturday] with two further races on Sunday.