Ford teams have claimed they are at a "continued disadvantage" for the Bathurst 1000 after proposed changes to their cars were rejected by Supercars.
Mooted aerodynamic adjustments to the Mustangs have been knocked back ahead of Sunday's race, prompting a strong response just hours before practice begins at the famed Mount Panorama circuit.
In a rare show of unity, all Ford teams - led by Shell V-Power, Walkinshaw Andretti United and Tickford - came together to issue a joint statement on Thursday about what they deem a lack of parity with their Chevrolet rivals.
"The independent data shows that the Mustang will be at a continued disadvantage for the biggest race of the year, which we believe is unacceptable - and not what our sport is built upon," the statement said.
"While disappointed in the situation, every Ford team will be doing their utmost this weekend, it's what the fans deserve, it's what our partners deserve, it's what the great race deserves.
"We will continue working together to correct the imbalance going forward, but for now, our attention turns on track, respecting the challenge that the mountain provides."
In the first season racing with Gen3 cars, Chevrolet Camaros make up the top five in the championship standings, with Shell V-Power's Anton de Pasquale the best-placed Ford driver in sixth.
Supercars said a parity review system has been in place all year, with a trigger point deemed to be five consecutive races, or five out of eight, with the required number having "not been met at this time".
"Supercars received a request from the Ford Homologation Team to implement a parity adjustment in advance of the Bathurst 1000," the organisation said in a statement.
"After numerous meetings with all teams and key stakeholders, the requisite consent from the Supercars teams has not been established to support the requested parity adjustment for the 2023 Repco Bathurst 1000."
