Supercars will hold four cars back following this weekend's The Bend SuperSprint, with a car each from Tickford Racing, Dick Johnson Racing, Triple Eight and Erebus.
The two Fords are expected to focus on back-to-back aero testing amid concerns over the drag numbers from the new rear package that was introduced in Townsville.
The new package was supposed to shift the aero balance rearwards and improve the rear tyre life on the Fords, however it has prompted some concerns over increased drag.
That could prove incredibly costly at the upcoming endurance races, particularly as both Sandown and Bathurst are high-speed circuits.
Bathurst would be a particularly difficult circuit to face a speed deficit at, given much of the passing happens at the end of Mountain Straight and into The Chase at the end of Conrod Straight.
Aero isn't the only item on the testing agenda, with a new tyre construction to also be trialled.
It is thought it will come from Goodyear, which is the parent company of Supercars control tyre supplier Dunlop.
Tyres have continued to be a hot topic since the move to the Gen3 cars with overheating seemingly an ongoing issue.
It appears some of the benefit from reducing dirty air with less aero is that the low-downforce cars move across the road more and overheat the tyre.
The tyre running is likely to fall to Erebus, as GM homologation team Triple Eight focusses on a fix to the steering rack issues that have plagued the new Gen3 cars.
The solution on trial involves strengthening the current racks rather than introducing a whole new part.
