Moir jumped first in the second race and may well have been a tad complacent knowing he had a points buffer and allowed Lower Hutt's Jay Lawrence (GSXR1000) to glide by.
Lawrence scorched to the finish line for the race two win in the fastest lap time of the day to give him pole position in the Robert Holden Memorial.
Mettam and Fitzgerald raced back in the pack in race two, but Mettams did enough to claim second in the series, while consistent performances at Whanganui gave Honda rider Mitch Rees third overall in the series. He is son of defending series champion Tony Rees who was out injured.
"It's all about the start at Whanganui. Once you are in front its hard to get passed," Moir said.
"I love street racing, especially Whanganui, but I've only ever won one race here before today. In the first race the road was still a bit cold and a bit slippery after the early shower, but it soon improved.
"In the second race I was mindful I had a points buffer for the series and next minute Jay was passed me. I was glad to hang on though and win the title, that was a great feeling.
"Not many people get to win the Robert Holden, so I made sure I got a good start in that. Daniel won the start, but went too wide on turn two and you can't do that - I managed to slip under him and take the lead, while he dropped a few more placings," Moir said.
The Robert Holden is open to riders with the fastest laps of the day in all classes except super moto, the newly-introduced Suzuki Gixxer 150 category and of course sidecars.
Moir won with Lawrence hard on his heels in second with Formula 2 series winner Shane Richardson from Wainuiomata taking third on his Kawasaki ZX6R.
Hometown racer Richie Dibben (Honda CRF450)reclaimed his super moto series title with two emphatic wins beating old foe Duncan Hart from Tauranga. Hart had won the title for the last three years in a row after Dibben had experienced a run of mechanical problems.
There were no such problems this season and with the trophy back with its rightful owner Dibben can also claim a three peat of wins in the class, however, nut in consecutive seasons.
More on the Cemetery Circuit in tomorrow's Chronicle.