The titanic battle between the Red Bull HRT and Shell V-Power Racing has continued in Friday practice at Hidden Valley.
A 1:06.04s effort from Jamie Whincup was enough to edge Scott McLaughlin by just 0.035s in the dying moments of the day's second 45 minute session.
Craig Lowndes underlined Triple Eight’s form with third, only 0.044s behind the six-time champion in the final green tyre runs.
"The car's good," said Whincup, whose team tested alongside the Shell V-Power Falcons at Queensland Raceway ahead of the event.
"We're obviously changing it up heaps. We can't just sit on our hands and cruise around.
"Definitely the car's better, we made improvements after the test day. Hopefully that continues on for the rest of the weekend.
"But there's always plenty of time for everyone. If we can find time I'm sure everyone can."
Scott Pye gave the Mobil 1 HSV Racing squad a solid platform to build from in fourth ahead of Erebus Motorsport’s David Reynolds.
Reynolds spent a significant period at the top of the order thanks to a 1:06.30s set on old tyres midway through.
He was bumped from P1 five minutes from the end by McLaughlin and failed to improve late, locking up and running off at Turn 5 on his new rubber.
McLaughlin had threatened to go fastest just past the halfway mark, quickest to the end of the second sector before making a mistake at Turn 11 and running across the grass.
"I want to be fast, but at the end of the day, the car is nice," the Kiwi said.
"I just overdrove it trying to find the limit in areas where we overstepped the mark.
"It's what practice is all about. We'll push it tomorrow and learn a lot.
"The car has been fantastic all day in race trim and qualifying trim. I'm just looking forward to tomorrow."
Nick Percat and Tim Slade were sixth and eighth respectively for Brad Jones Racing, sandwiching James Moffat in the lead Garry Rogers Motorsport Commodore.
Shane van Gisbergen had an off at the final turn during the session on the way to an eventual ninth ahead of Tekno’s Will Davison, who made it nine Holdens in the top 10.
Mark Winterbottom was the top Prodrive Ford in 12th, one place ahead of McLaughlin’s team-mate Fabian Coulthard.
Nissan’s promising Practice 1 form failed to continue, with early pace-setter Rick Kelly the best of the Altimas in 16th.
Wildcards Jack Le Brocq and Macauley Jones rounded out the 28-car field, which was separated by just 1.2s.
Click here for the full results.