Winterbottom is the first person to hold the Jason Richards Memorial and the Peter Brock Trophy he won at Bathurst last year with a slender points win over Kiwi hero Scott McLaughlin. Winterbottom's young team-mate Chaz Mostert was third in the longer 200km race.
The Pepsi Max Crew FPR driver now has a 107 Championship point lead over Red Bull Racing Australia's Craig Lowndes who is 10 points ahead of Lockwood Racing's Fabian Coulthard. Reigning Champion Jamie Whincup is 166 points back in sixth.
Lowndes finished in twentieth today with Whincup in tenth.
As he said after his win on Saturday, Winterbottom intends to keep extending his lead at the next event in Perth which is followed by the SKYCITY Triple Crown in Darwin and the Townsville 500.
"I wanted to lead the Championship leaving here on Sunday. I didn't want to lead on Friday and someone takes it back off you on Sunday. We now have two weeks to enjoy it.
"Triple Eight are having a rough run which is surprising because (Shane) Van Gisbergen in the same car is going quite well. That's interesting.
"I am rapt they had a bad weekend and normally we don't capitalize on it when they do. But they've had two and we have out-scored everyone both times. We are getting it right at the right time.
"Hopefully we can maintain it. It is good that Chaz and Dave are doing well – we have more cars up there doing well. The more we have up there the more we take points off everyone else."
In a race which did not feature a single safety car period Winterbottom and McLaughlin dueled out in front all day with only the final stop of the day determining the outcome. It snared Winterbottom the treasured Trophy for the best performed over the Anzac weekend.
"That's amazing. The Jason Richards Trophy in particular is very special. He was an amazing guy. To win it is very special. I am holding this one and the workshop have got the Peter Brock Trophy for Bathurst. It is pretty cool. I was rapt to win this and very honored to win it," Winterbottom said.
"To race on Anzac Day was really special. To see the crowd – Friday seemed like a Sunday. That was awesome and to race three days was great. If you were a fan you would love it. It was an amazing weekend."
Winterbottom beat McLaughlin out of the pits at the last stop, having entered behind the young Kiwi. It appeared a case that Winterbottom took slightly less fuel with his team doing a great job to get him to the front.
Not only did they exchange the places it also swapped the lead in the Jason Richards Trophy hunt, putting Winterbottom narrowly in front.
McLaughlin was 'shattered' to miss the Jason Richard's Trophy by a place.
"Yeah, that's what happens," he said.
"It was a pretty good battle up until then but actually, I thought we might have edged in front of Frosty because we probably took on a little more fuel at the first stop but yeah, he got me.
"Our car was set up for a first stint, we didn't really compensate for the track ripping up so you know, come back here next year, we'll have a bit of thinking to do, but we've got a direction."
Heartache struck for Supercheap Auto Racing's Tim Slade when he lost clutch control on the starting grid, a devastating blow for the Holden driver who had just celebrated scoring a front-row start next to McLaughlin.
The initial start was aborted when Slade began waving his hands just as the starter's signal was about to come on. The field did a second formation lap with Slade heading from the front row to pit lane, a terrible blow for the popular Gold Coaster.
Yesterday's winner Shane van Gisbergen, Nissan's Michael Caruso, Jason Bright, Erebus' Will Davison, Rick Kelly, Fabian Coulthard and Whincup completed the top 10.
Others to note include Garth Tander 12, James Courtney 14, David Reynolds 17 after a great start and setback with a punctured tire, and Lowndes 20th – another tough day for the Red Bull Racer.
The V8 Supercars will next hit the track at the Perth 400, from May 16-18 at Barbagallo Raceway.