The V8-powered series found itself dealing with controversy following the latest round of the national series at Queensland Raceway.

The controversy was sparked by the rear windscreens on the Garry Rogers Motorsport-run cars, which were flexing at speed.

GRM driver and runaway series leader Nathan Herne later admitted it was a deliberate ploy, achieved by purposely loosening the struts under the windscreen.

The Queensland-based TA2 series, one of two Trans Am administrators in Australia, reacted first, banning loose struts ahead of its round at QR this weekend.

The national series has now followed suit, issuing a technical bulletin to competitors that strictly outlaws purposely leaving struts loose.

The new rules come into effect ahead of the next round at Sandown in mid-September.

"It is prohibited to modify or manipulate any bodywork mounting structure," reads the bulletin.

"Each bodywork mounting structure (ie support strut, primary or secondary frame, or other structure) must be fitted as per the manufacturer’s specifications, including any mounting structure locking mechanism, in its entirety.

"Accident damage repair must ensure compliance with this regulation or as otherwise authorised at an event by the TD, in which case the TD will be the sole arbiter during an event with regard to the interpretation and application of these regulations and any decision made by the TD in this regard will not be the subject of any protest."

The bulletin also addresses some significant technical changes that will come into effect for the 2023 season.

One is reducing the tolerance on the wheelbase from +/- 25.4mm to +/- five millimetres.

That is a response to increased rear gearbox seal and rear bush wear as teams look to maximise the tolerance.

Teams will also be forced to leave the front splitter mounted in its factory location, and it can't be lower than the line between the bottom of the chassis rails and front cross member, or 19mm higher than that line.

The splitter will be limited to 13mm rake.

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