2023 Australian Formula Open Series

The 2023 Australian Formula Open - powered by Racefuels was a multi-event open-wheel single seater motor racing championship. This was the inaugural season of the championship, founded by two-time Australian Gold Star winner Tim Macrow as a direct successor to the Australian Formula 3 championship.

Drivers competed to win a S5000 test and free entry to a race in the S5000 Championship in 2024 or later.

Trent Grubel, driving for Tim Macrow Racing, won the overall championship and with it the AFO1 class championship, three points ahead of his teammate Ryan How. Matthew Roesler, driving for his privateer State Fleet Services team, won the AFO2 class championship, while AGI Sport's Kristian Janev was victorious in the AFO4 class.

Teams and drivers
The championship was structured in four classes, albeit only three classes received entries through the season. AFO1 encompassed all Formula 3 machinery, with several chassis and engine manufacturers represented. AFO2 catered to Toyota Racing Series, Formula Renault and older F3 cars. AFO3 served all other invitational entries, but did not receive any entries, while AFO4 was reserved for Formula 4 cars.

Race calendar
The 2023 calendar was first announced on 20 December 2022. It consisted of six rounds across six circuits all over Australia.

Season report
The inaugural Australian Formula Open series kicked off at Winton Motor Raceway. A conjoined grid with the NSW Formula Car Championship saw 19 entries tackle the weekend, and Tim Macrow Racing's Trent Grubel took pole position for the first race. He converted that to a win ahead of his teammates Winston van Laarhoven and Ryan How. Grubel went on to sweep the weekend, with the podiums of both other races completed by 99 Motorsport's Ryan Astley and How. AGI Sport's Kristian Janev also took a triple win in the AFO4 class to take the class lead ahead of his teammate Mark Wilson.

Round two was held at Sydney Motorsports Park, again in conjunction with the NSW FCC. Grubel was once again on pole position for the first encounter, but multiple crashes at the race start led to the race being abandoned and later declared a non-event. Grubel was undeterred by that and went on to win the other two races, remaining as the only AFO1 winner of the season. How took both second places, with Gilmour Racing's debutant Jon Collings taking two third places. Janev and his debuting teammate Brodie Norris shared wins in AFO4, while the AFO2 class also took off, with privateer entries Matthew Roesler and Paul di Biase taking the honors.

The first half of the season closed at The Bend Motorsport Park. Grubel continued his pole position streak, but the formbook for the races was rewritten: How became the second race winner in the series as he was the fastest driver throughout all three races to sweep the weekend. Grubel held on to second ahead of Astley in races one and three, but only managed to finish fourth in the second race, with his teammate Miles Bromley third behind Astley. Brodie Norris continued his run of form to sweep the weekend in AFO4 and shorten his gap to Janev. Debutant Christopher Slusarski won all thee races in AFO2, while class leader Di Biase did not finish any of the races.

Queensland Raceway was up next, and How ended Grubel's pole position streak. He dropped to third in the first race though, allowing Grubel to take the win and Chris Gilmour, debuting for the eponymous team, into second. The second race proved even worse for How, as a bad start saw him drop off the podium and allowed Bromley onto it. How was back on top for the feature race though, but Grubel still extended his points lead. AFO2 saw no entries for the round, while AFO4 class leader Janev had an atrocious weekend with a retirement in the first race not allowing him to take part in the rest of the weekend. The chasing Norris took two wins and his teammate Peter Bouzinelous claimed one.

How took a second pole position at the penultimate round at Sandown Raceway. Him and Grubel finished 1-2 in the first two races, with Grubel taking both fastest laps to minimize the damage to his points lead. Their positions were flipped for the final race, but How still reduced Grubel's advantage to 20 points. Bromley took two more podiums to get closer to third place, with TWS Motorsport's Trent Shirvington also appearing on the rostrum. Roesler was the only entrant in the AFO2 class, so he took two more wins to extend his lead, while Norris and Janev continued their tussle in the AFO4 class, with Norris taking two wins to reduce Janev's lead to only three points.

How needed a perfect final weekend at Phillip Island to deny Grubel the title, and did everything he could by winning all three races and taking two bonus points for fastest laps. Grubel could only manage second, third and fourth in the races. Crucially though, he was able to take pole position and claim the fastest lap for the first race. That saw him take the overall and the AFO1 title by three points. Bromley took three podiums to narrowly secure third ahead of Astley. Both AFO2 and AFO4 were decided in absence of the champions, with Roesler taking the AFO2 crown and both Janev and Norris absent from AFO4 competition, allowing Janev to claim the title.

Opening up competition to more classes of formula cars proved to be a huge success, as the series' meetings regularly attracted deep grids. While competition in AFO1 and AFO4 initially seemed to be rather lacklustre, How and Norris were able to close up to the respective leaders Grubel and Janev to provide two close championship battles. With the series planned to be expanding in both round numbers and national and international coverage in 2024, the only question left open is if the championship will really be able to serve as a feeder series to higher-level competition.

Scoring system
Cars classified as finished in race 1 and 2 were awarded points by the following structure: The third race of the weekend, the longer Feature Race, awarded more points: