It was a clinical performance for the Kiwi, who matched his times – to a ten thousandth of a second – in Q2 and Q3 in the knock-out session.
The time was only good enough for fifth in Q2, but a decision to run early in Q3 to combat rising ambient temperature proved critical as a 54.3625s became good enough for pole.
"It was pretty good," said van Gisbergen. "Thanks to [engineer] Andrew [Edwards] for loading the hot doc in the thing. We really struggled yesterday and today it came alive.
"I feel like I'm wobbling, I can't drive the thing. I just drive around and do what it does, it's all on the team, so thanks to them."
Series leader Kostecki fell 0.02s short of van Gisbergen to qualifying second and set up a juicy front row for the opening race.
David Reynolds, who was quicker than the pole time in Q2, fell back to third in Q3 after battling a shift cut sensor issue that meant he had to use the clutch on his upshifts.
Jack Le Brocq and Matt Payne both impressed as they qualified fourth and fifth respectively, ahead of James Courtney and Will Davison.
Thomas Randle, Tim Slade and Bryce Fullwood rounded out the top 10.
The knockout format claimed some big names with the middle segment tripping up the likes of Chaz Mostert, Anton De Pasquale and Cam Waters.
Mostert was outqualified by Walkinshaw Andretti United teammate Nick Percat for just the second time, the pair ending up 14th and 15th.
De Pasquale was well behind his teammate Davison with 18th on the grid, while Waters was the worst of the four Tickford Mustangs way down in 19th after a lock-up at Turn 1 on his critical lap.
Andre Heimgartner, meanwhile, didn't even make it through Q1, the Brad Jones Racing team leader 21st on their grid.
Will Brown, who along with his Erebus team came into the weekend in good form, will start from 22nd.
