The Australian series was rocked by a pair of spectacular engine fires at the recent Albert Park round with both Nick Percat and James Courtney's cars going up in flames.
Through investigations followed that Melbourne event, the outcome of which was a change to the catch can breathing system.
The breather now feeds out to the rear of the car rather than in the engine bay to avoid the vapour build-up thought responsible for fuelling the fires.
An additional measure has also been mandated for Perth with all cars now sporting white paint on the upper surface of the inner wheel guards.
The surface is a two-part fire retardant epoxy which is believed to have aerospace credentials.
Absorption of flammable substances by the composite guard was thought to have contributed to the fires.
All cars will debut the paint when they hit the track for the first 90-minute practice session in Perth tomorrow.
