Jamie Whincup made it two from two in the second V8 Supercars race at Hidden Valley.
Whincup led from pole, and after fending off fast-starting Triple Eight team-mate Lowndes, was never in any danger and sailed to victory by 3.398 seconds over birthday boy Lowndes.
Whincup had ended a barren streak in the first race of the day, after going winless since round five at Symmons Plains in March, where he had also taken a double win.
Fabian Coulthard continued his impressive season so far in the Brad Jones Holden, rounding out the podium - although he looked powerless to match the pace of the Triple Eight pair. Following him was Garth Tander, who moved up from a sixth place starting berth early on.
Championship leader Mark Winterbottom came home sixth behind the Volvo of Scott McLaughlin.
Winterbottom had dropped down the order after some aggressive wheelspin at the start, but fought back in an impressive display to limit the damage done to his points lead.
Shane van Gisbergen struggled to match his pace from the earlier race, in which he pushed Lowndes for second and scored a podium. He could only manage seventh.
Results - 35 laps:
Pos Driver Team/Car Time/Gap
1. Jamie Whincup Triple Eight Holden 42m26.1100s
2. Craig Lowndes Triple Eight Holden +3.3980s
3. Fabian Coulthard Brad Jones Holden +5.8647s
4. Garth Tander HRT Holden +11.5143s
5. Scott McLaughlin GRM Volvo +12.9071s
6. Mark Winterbottom FPR Ford +13.2593s
7. Shane van Gisbergen Tekno Holden +13.6915s
8. Tim Slade Rosenberg/HRT Holden +15.4797s
9. David Reynolds Rod Nash/FPR Ford +16.4292s
10. Michael Caruso Nissan +18.4943s
11. James Courtney HRT Holden +20.3551s
12. Jason Bright Brad Jones Holden +23.0618s
13. Will Davison Erebus Mercedes +23.6105s
14. Chaz Mostert FPR Ford +24.7298s
15. Scott Pye Dick Johnson Ford +25.1103s
16. David Wall Dick Johnson Ford +30.1433s
17. Dale Wood Britek/BJR Holden +32.3863s
18. Robert Dahlgren GRM Volvo +32.7773s
19. Nick Percat Walkinshaw/HRT Holden +35.3481s
20. Jack Perkins Schwerkolt/FPR Ford +43.7753s
21. Russell Ingall Dumbrell Holden +1m03.8822s
22. Rick Kelly Nissan -1 lap
23. Todd Kelly Nissan -1 lap
Lee Holdsworth Erebus Mercedes 8 laps
James Moffat Nissan 0 laps