There was a heart-in-mouth moment in the opening minutes of the co-driver practice during a Full Course Yellow rehearsal.

While other cars slowed on Conrod Straight, the #2 Walkinshaw Andretti United and #26 Grove Racing Ford Mustangs continued unabated before suddenly slowing.

Coulthard locked his right front, sending smoke signals behind him. Then Wood arrived at speed and was forced to suddenly slow and take evasive action.

He veered to the left, taking to the grass to avoid hitting the preceding Ford Mustang.

In its findings, Motorsport Australia noted both the #2 and #26 cars continued at full throttle despite yellow flags and FCY boards being displayed.

No penalties were delivered given the circumstances, as outlined by Motorsport Australia in its summary of findings. However, Motorsport Australia said it would not hesitate to deliver a penalty in the race.

“This incident should stand as a reminder to all Drivers that the commencement of a FCY or SC deployment requires them to noticeably reduce speed,” the summary read.

“Drivers should be aware that a Car ahead may at any point in the 25 second window elect to have activated their limiter and reduced speed to 80kph and, unless the following Cars react accordingly by reducing to a corresponding speed, a collision may occur.

“Given that the incident occurred during a test and in a Practice session, in this instance the Stewards determined to impose a Warning on the Driver of Car 26. However, this should not be seen as a precedent Penalty for similar infringements in a Race.”

Despite plans for Supercars to up the Full Course Yellow speed from 80 km/h to 120 km/h, officials decided against the move.

An amendment was made to the rules before Practice 4 that increased the slow-down warning from 15 seconds to 25 seconds. Competitors were advised by Motorsport Australia.