Red Bull Holden driver van Gisbergen was unstoppable in the first 11-lapper, the Kiwi taking a lights-to-flag victory.
He wasn't quite able to shake Anton De Pasquale, but had enough pace to cover the Erebus driver's single-lap overcut attempt during the compulsory stops.
The gap between the pair was 1.5s at the finish.
Scott McLaughlin was a lonely third, the DJR Team Penske star unable to match the lead pair, falling 4s behind, but easily quicker than teammate Will Power in fourth.
Lee Holdsworth and Chaz Mostert were fifth and sixth, Garry Jacobson, Andre Heimgartner, Will Davison and Jack Le Brocq rounding out the Top 10.
Norris had been in the mix for a solid Top 10, only to be slapped with a drive-through for hitting Cam Waters right after the stops.
The Formula 1 driver then toured the lane again, happy enough to drop down to third last – and take third on the grid for the second heat.
The gamble on grid position paid off for Norris, who dominated the reverse-grid affair.
It did take him four laps to clear Todd Hazelwood, but once in front Norris was able to cruise to victory as the other front-runners battled through the pack.
His final winning margin was nearly 3s over Waters and Hazelwood.
"It was good fun," said Norris. "After the drive-through [in Race 1] I needed to take advantage of starting [at the front] and going for the win in this race.
"I had decent pace, it was a nice little win."
De Pasquale was best of the Race 1 front-runners, an early stop and long second stint yielding fifth.
Van Gisbergen went the opposite way on strategy, pitting just three laps from the end en route to seventh, behind Bruce Fullwood.
McLaughlin had a shocker in the second race, starting when he couldn't avoid a stranded Chris Pither at Turn 1.
He then spun again later in the race, 18th as far as he could recover.