Motorsport.com has learned that for at least the first part of this season drivers won't be able to manipulate the front or rear roll bars on the fly.
Roll bar adjustment will instead only be able to be made under the car during pitstops, similar to the system used in GT3 racing.
This is the second time Supercars has moved to stop in-car bar adjustment, the series having considered dropping it for good as part of the early development of the Gen3 rules.
That was part of a push to simplify the cars and cut costs.
This time, however, the move has to some extent been forced on the series due to the time constraints on the Gen3 builds.
Teams are already facing delays to their testing programmes, with some not expecting to have their Gen3 cars on track until the middle of February – just weeks before the season kicks off in Newcastle.
Supercars has therefore decided to put its focus into car builds and will investigate the introduction of in-car bar adjusters at some point later in the season.
The cable-operated brake bias adjustment will carry over from the old car to the new car, however 'quick change' systems, which allowed pre-programme bias positioning, will be banned.
Motorsport.com understands there is another rule change regarding spare parts in the works.
The Gen3 cars feature front and rear clips, which are bolt-on chassis structures designed to make repairs faster and easier for teams.
Supercars is, however, set to formalise rules that will determine how complete a spare clip can be in terms of what can and can't be attached to it when it sits in the truck or garage during a race weekend.
The Supercars Commission will discuss and decide on the definition of a complete clip before the opening round of the 2023 season.
