A decision to enforce further changes to Ford's all-conquering Mustang has provoked a response by defending Supercars champion, Kiwi driver Scott McLaughlin.
Supercars analysis determined the Mustang holds an aerodynamic edge over its Holden and Nissan rivals.
Led by DJR Team Penske star McLaughlin, the Mustang has won nine out of 10 races in 2019 and eight pole positions.
Its dominance has led to rivals claiming it has an unfair advantage and now the cars must undergo changes before next week's event in Perth, mainly to the rear wing.
"Nothing like fire in the belly," McLaughlin tweeted when the news of the enforced changes was made.