HRT's Garth Tander won race 14 of the V8 series on Sunday, after team mate Will Davidson won on Saurday
HRT finished 1-2 in Sunday's 200km race with Tander and Davison relegating Ford's Jamie Whincup to third.
Whincup's championship lead has been cut to 117 points ahead of Davidson at the midway point of the season.
Tander remains in third place just ahead of Triple Eight’s Craig Lowndes.
Tander's second victory of the season was helped by a perfectly timed pit stop just before a safety car period, allowing for a re-fuel, new tyres and vital track position.
Tander had got off to a flying start from sixth place on the grid in the 65-lap race, using the new soft compound sprint tyre to good effect.
He kept those tyres on until lap 29 when he made his race-winning pit stop, then defied a voltage problem which heavily sapped his car's power in the final laps.
"We've had a few races lately where the strategy's been to zig and we've zagged, so it's great for us to get it right," Tander said.
"There wasn't a lot of engine going on in the car at the end - it was just get the car home. I was surprised we lasted the full distance to be honest, it was a fantastic result."
The next two races in the series will be held at Queensland Raceway from August 21 to 23.