Two Mustangs spectacularly caught fire in consecutive races at the Beaurepaires Melbourne SuperSprint, specifically those of Walkinshaw Andretti United's Nick Percat and Tickford Racing's James Courtney.
After the front-left corners of each car went up in flames on the opening laps, a host of emergency measures were implemented ahead of the weekend finale at the Formula 1 Rolex Australian Grand Prix event.
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Among them were a change to the venting of the catch can, piping it towards the bottom of the vehicle instead of letting fumes vent into the engine bay.
The change was compulsory for the Mustangs and optional for the Camaros, while Supercars also opted for the following race to be started from Safety Car conditions.
Now, following a further meeting of the Gen3 Technical Working Group, it is understood that a further tweak has been agreed.
In essence, it is a modification of the ventilation change made during the Albert Park weekend, namely a longer hose to disperse fumes further away from the engine bay.
Furthermore, the new specification will apply to all cars for next week's Bosch Power Tools Perth SuperSprint, rather than the Mustangs only.
The catch can will remain in the same location, but the risk of a build-up of vapour near hot componentry such as the exhaust no longer remains.