The test will run throughout the week with the findings used to finalise and homologate the aero packages for both the Mustang and Camaro.
The programme is being shared between the Supercars technical team and the two homologation teams, Triple Eight Race Engineering (General Motors) and Dick Johnson Racing (Ford).
As for driving duties, that's being shared between Porsche Carrera Cup ace Bayley Hall and Routley, who doesn't compete but has been the safety car driver for almost a decade.
Hall and Routley will split their time between the Mustang and Camaro.
The VCAT process involves fitting the cars with sensors and completing straight line runs.
Variables such as ride height and speed are altered to assess how the cars perform aerodynamically.
The process was famously improved back in 2019 when the Gen2 Mustang and Commodore had to be re-homologated a number of times during the season.
That was triggered by a dominant start to the season for the Mustang, which replaced the Ford Falcon.
The aero homologation is a critical part of the Gen3 development ahead of the debut of the new cars at the Newcastle 500 next March.
Control chassis are now flowing in both complete and kit forms from supplier Pace Innovations as teams begin their builds.
Supercars has consistently aimed to have all teams testing with at least one car next month, although there has been scepticism from some teams if that will be possible.