Car #25 completed four pit stops on Sunday. Image: Supplied
The #25 Ford of Mostert and Fabian Coulthard was the only front-runner to tackle the extra stop and twice led the race as a result.
However, they ultimately finished in eighth place and 32 seconds behind the winner after a 102-lap journey devoid of any Safety Car periods.
Still, that was enough to put Mostert’s already near-certain position in the finals beyond doubt before next month’s Bathurst 1000, which marks the last regular season event.
WAU principal Carl Faux was race engineering the #25 entry on Sunday and said the team knew it was in trouble relatively early on.
“Chaz was fairly secure in the finals series so we thought we’d roll the dice,” Faux told Speedcafe.
“We expected there to be a faster race pace to be honest and higher deg than there was.
“We knew from about a third of the way in that wasn’t going to be the case, but we were already committed to the four-stop.
“It obviously smashed everyone who did a four-stop. It was the riskier strategy and we didn’t have a fast enough car to make it work.”
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According to Faux, the team had planned the strategy from early in the weekend, setting aside tyres to enable it to execute five stints.
The Brit only took over race engineer duties on the car for Sunday after Mostert’s regular right-hand man Sam Scaffidi returned home on Saturday night for family reasons.
“I don’t usually look at any data of this car or set-ups,” explained Faux, who graduated from technical director to team principal in late 2023.
“Usually what I do is make sure they are all talking the right language at the same time and going through the right processes.
“So I know the process and I know what is required to be done but it was a late [Saturday] night trying to get up to speed on where the car had ended up and the ideas going into [Sunday].
“The decision had been made in the lead-up, that’s why there was so many green tyres available for car #25. It was about executing what was there.
“The pit stops were good, we tuned the car up in the race which we were happy about, but just not quite fast enough.”
Faux affirmed that damage to the rear bumper of the car impacted its straightline speed – ironically adding drag to a Mustang aero package that had been revised to achieve the opposite.
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However, information from earlier in the weekend leaves WAU hopeful the Fords can be competitive at Bathurst.
“From what I could see in the lead-up to the race the straightline speed looked better, it looked like it was a match [for the Camaro]. Hopefully that still continues at altitude,” he said.
“As everyone can see the cars have been different and everyone wants it to be fair at the Mountain. Let’s hope that’s what’s been achieved.”
Mostert’s #25 entry has finished fifth and the second Ford home in the two Bathurst 1000s run under Gen3 regulations to date.
This year will mark WAU’s third and final Great Race with Ford, with demonstrations of the team’s new-for-2026 Toyota Supra due to take place during the weekend.
Dick Johnson Racing, Tickford Racing and Grove Racing – which had all taken part in pre-event testing of the Ford aero package revisions – led a Ford podium sweep at The Bend on Sunday.