A championship-changing day has turned the Porsche Paynter Dixon Carrera Cup Australia title fight on its head as a pair of Michelin Junior driver stars took the trophies on the streets of Townsville.

Team Porsche New Zealand young-gun Callum Hedge won Round 4 of the championship, while earlier in the day Jackson Walls claimed the Enduro Cup race to make it two first-time winners in two races in a chaotic Sunday of racing in North Queensland.

Former champion David Wall finished third to take a huge chunk of championship points out of leader, Harri Jones, who had a tough weekend.

In MORRIS Pro-Am, Geoff Emery converted his pole position and race one win to another pair of victories on Sunday to complete a clean sweep of Round 4. It's the first time anyone has swept the weekend in Townsville in the Carrera Cup 'race within a race'. Stephen Grove and Dean Cook completed the podium.

Hedge is the fourth different winner from four rounds this year as a fiercely competitive championship reaches its half-way point.

The day started with a fiercely competitive Enduro Cup encounter on Sunday morning, won superbly by Jackson Walls in his Objective Racing Porsche.

Starting from second, the young Sydneysider made a perfect start to out-drag Luke Youlden into the first corner.

From there he withstood pressure from the Race 1 winner, Callum Hedge, David Wall and Aaron Love in a furious battle to the line, to claim his maiden Carrera Cup victory in just his eighth round.

Hedge was second, taking advantage of a last-lap bump at turn three between Walls and Youlden, that saw the latter slowed and enabling the Kiwi to charge past.

Youlden would grab third with Wall fourth and Love in fifth, with the contact between Walls and Youlden called a racing incident.

Ryan Suhle, Brad Shiels, Duvashen Padayachee, Angelo Mouzouris and Harri Jones completed the top-10.

Emery pulled clear of former Townsville winner Stephen Grove to claim the victory in MORRIS Pro-Am, with Liam Talbot third. Dean Cook and Rodney Jane completed the top five in class.

The final race of the weekend was just as dramatic as Walls and Hedge drag-raced down towards turn two, having made equally impressive starts. The two juniors ran side-by-side through the first four corners before Hedge was able to wrestle his way into the front.

Walls would later lose two further spots to Wall and Love to finish fourth, a moment that ultimately the deciding factor handing Hedge the round win overall in just his sixth Carrera Cup round.

It's the second time in two years Carrera Cup has delivered three winners from three races in Townsville.

Walls' finished second overall to further enhance his weekend of firsts, while David Wall's second in the race and overall round podium finish, represented his first time in the top three in Townsville in any category.

Hedge and Walls were both on the outright podium for the first time in Carrera Cup.

Love finished third in the race, however faces a post-event investigation following contact with Luke Youlden that sent the Tekworkx Motorsport car spinning at turn 7 - ending his otherwise strong run to a round podium and dropping him to 24th position.

Championship leader Harri Jones finished 10th and 7th in the two races, respectively, to see his 114-point championship lead pre-round reduced by a significant margin to just 39 over David Wall heading into the second half of the season.

Dylan O'Keeffe sits third with Dale Wood and David Russell completing the top five.

Emery's path to a third straight MORRIS Pro-Am win came ahead of Steven Grove and Rodney Jane, while key title contenders Sam Shahin and Liam Talbot both struck dramas. Dean Cook's fourth position was enough to give him the point to secure a spot on the podium.

Emery's round win was the third Pro-Am win of his Carrera Cup career and makes him the first repeat winner of the season, the Victorian having won at Albert Park earlier this year.

He now takes a 17-point lead in the Pro-Am class over Stephen Grove into the next round, with Dean Cook climbing to third

The Porsche Paynter Dixon Carrera Cup Australia Championship returns in three weeks time at The Bend Motorsport Park in South Australia, racing at the OTR SuperSprint on July 29-21.

Callum Hedge, Round 4 Pro winner:

“Really stoked, got really lucky at the start, got a really good launch and passed Jackson across the third and fourth corner. I knew David Wall was on green tyres so I was hoping he could get held up for a few laps, but when he got to me, he couldn’t get passed. It’s hard to pass in this car with the aero wash around this street circuit. I just want to say thanks to the Earl Bamber Motorsport boys and Team Porsche New Zealand for a really good car and I can’t thank everyone enough. I’m absolutely stoked to win, I’ve been really unlucky the last few rounds, finally fourth time lucky we did it.”

Jackson Walls, Race 2 Pro winner:

“It’s definitely weird to get my first race win here, I didn’t expect it, especially being my first time in Townsville and one of the only rookies, but I’ll take what I can get. I couldn’t be happier with the team and everyone who has supported me to get where I am today, it’s been a long two years through Covid, but I couldn’t be happier.

"We had a tyre disadvantage due to the fact we used our new set yesterday, it was all good until they started to go with five laps still left to go, so I was struggling to get the car on the apexes and locking up everywhere. The battle with Luke (Youlden) I was just trying to defend and I was really hungry for the win and kept telling myself I’m going to win, so wasn’t give it up easily.“

Geoff Emery, Round 4 Morris Pro-Am winner:

“It feels really good, it all started in the practice, I had solid qualifying sessions and then three strong races, it couldn’t have been a better weekend for us. In the race I broke away pretty early and just managed the gap, I had a really good car and plenty car speed.

“Townsville is not without its incidents and there was a couple going on there (in Race 2) which brought out the safety car. That cooled the tyres right off, but once the tyre came back up (to temperature) they were good. But otherwise it was a really good race for us and for the last race it will be a lot hotter, so we’ll adjust the pressures. The car has been really good throughout the whole weekend and I think we’ve made the right decisions so far.”