He pushed Courtney hard but couldn't find a way past late in the race when his tyres started to go off.
Courtney's tyre-life was much better and he eased to victory.
Australian Kaidon Brown made steady progress through the race and eventually finished third.
The best of the Kiwis was Aaron Hodgson, who started off the pole but placed fifth.
Matthew Leversedge secured a terrific win in the sprint car feature to beat Auckland's Daniel Eggleton, with Pickens third.
Jeremy Webb took out the TQ midget feature, beating Ryan Barry by over a second. Ben Morrison came home third.
In the F2 midgets, Corbin Anderson snapped Mitch Osborne's run of feature wins. Osborne secured second place, while Leyton Kendall finished third.