Craig Lowndes made up for a horror Saturday, when his left rear tyre exploded, spinning him on the front straight, for second yesterday. Scott Pye earned a first podium finish with third place.
"I'd be lying if I didn't tell you there was a little bit of emotion during the final few laps," said Whincup.
"I was a teammate of JR's [Jason Richards] and I haven't won anything this year. So it's nice to come away in 2015 with one of the bigger prizes of the year - The Jason Richards Memorial Trophy.
"It's been a bit of a dry spell by my standards but this weekend has been fantastic and I feel I'm back."
Championship leader Winterbottom was philosophical about his weekend, knowing he had the car speed but just couldn't convert it into a race win, or even a podium over the weekend.
"It's a bit frustrating, as the car was the best it's been in race mode all weekend [in Sunday's race] and then I go and get turned around and end up last," said Winterbottom.
"At least we salvaged something to finish 11th and only lost 18 points in championship."
New Zealand drivers Shane van Gisbergen and Scott McLaughlin showed they could be a threat on Saturday with a second and third respectively. But neither could convert their sprint race form into anything of substance during yesterday's race.
The best of the Kiwis was McLaughlin in sixth, followed home by Fabian Coulthard in seventh, van Gisbergen in ninth and Andre Heimgartner in 21st.
McLaughlin put his car on pole for the feature race, edging out Whincup by one-thousandth of a second, and had looked racy all weekend.
However, a rule change that stated all cars must start on soft tyres and then change to hards at the fuel stop put paid to any advantage the Volvo might have had staying on softs for any extended period. And double stacking during the stop didn't help the Kiwi's fortunes either.
"We rolled the dice on fuel but when the safety car came out, it stuffed our race," said McLaughlin.
"It was a tough gig but one of those things and we just have to push on. We've got good car speed and over the last two rounds, we've got a good shot at getting some good finishes."
Coulthard's team couldn't find his car's sweet spot all weekend and van Gisbergen just did not qualify well enough to make big inroads during the race.
Heimgartner, on the other hand, had slitter issues all weekend that messed with the car's aero and had a weekend to forget.