With Shama Putaranui in the navigator's seat, the pair then breezed through the rest of the afternoon before beating Australian Ted Sygidus and Rotorua's Nick Berryman by almost two seconds in the final top 3 eliminator.
It was back-to-back victories for Caughey, who also stood on the podium in Wanaka and now extends his lead in the overall championship.
Whanganui's hopes in the Superboat group were Rob Coley and Richard Murray. Both qualified well but were eliminated in the top 6 round which, aside from Caughey, was separated by about 0.6 seconds.
Ollie Silverton won Fowler Homes Group A to also record consecutive wins while Whanganui's Ross Travers, who was hot on his tail after round one, bowed out in the top 9 run, messing up the rotation after a long delay for the track to be cleared.
Usually about 3000 turn out at the Murray family farm which houses the Shelterview track and owner Julia Murray estimated about the same-sized crowd this year.
"It's a really hard one to estimate but I'd say we are around that," she said.
"It's looking like a good crowd anyway and, because we're finishing a bit later, people who are working can still come out after work and still have a couple of hours racing. So we could still have a bit of an influx."
Murray was pleased the weather had played its part.
"Especially when I heard the rain on the roof last night."