Kai Allen at the Perth Super440. Image: Supplied
Allen escaped punishment despite tyre pressure monitoring sensors (TPMS) recording two of his tyres below the required 16 psi minimum while on the grid.
While accepting the breaches occurred, Motorsport Australia stewards cited several mitigating factors in declaring that no penalty would be handed out.
That’s driven a strong reaction from rivals given the standard penalty is disqualification.
In excusing the 15.959 psi (right-rear) and 15.786 psi (right-front) readings, stewards noted there is an “acknowledged TPMS accuracy of 0.4 psi”.
Teams canvassed by Speedcafe noted they take potential inaccuracy of the sensors into account when setting their starting pressures.
The tyre pressure rule is essentially a safety regulation, stopping teams from risking tyre failures while chasing performance through low starting pressures.
Speaking on his Lucky Dogs Podcast, Dick Johnson Racing’s Brodie Kostecki claimed Allen gained an advantage from Grove Racing’s conduct.
Kostecki said his team typically starts its pressures at 16.5 or 16.6 psi to ensure they do not dip below 16 while on the grid.
The 2023 champion said a 0.7 psi difference at ambient temperature equates to around a 1.7 psi difference in pressure during a race.
“That’s probably three tenths a lap advantage, [or] two tenths a lap advantage,” he claimed.
“It’s huge because what the tyres actually race around to what we qualify them at is quite a big difference.
“This is quite a big performance advantage and I think a lot of people within the industry are shocked.
“It’s opened a big can of worms.”
Kostecki’s quoting of 0.7 psi appears to be the difference between his own claimed starting pressure of 16.5 and Allen’s recorded on-grid figure of 15.786 psi.
Stewards noted that all four of Allen’s tyres were at 16.32 psi when he left the team garage, and were above 16 psi when the race began.
Triple Eight driver and podcast co-host Will Brown also said Allen had a “massive advantage’ and declared his team is “extremely unhappy” about the lack of any penalty.
“Me and [engineer] Andrew [Edwards] discussed on Sunday night before we flew out, let’s just set our tyres at 16 psi,” he said.
“The precedent has been set that if they drop to 15.7, [as long as] by the end of the formation lap [they’re at the right pressure]….
“So we can start at 15.5 probably for the warm up lap and have 16.2, 16.3 for when the red lights go out.”
Interestingly, Edwards was the race engineer for Nick Percat at Brad Jones Racing during a previous tyre pressure controversy at Hidden Valley in 2021.
In that instance, BJR reported to Supercars officials that two of its tyres had dipped below the minimum pressure while on the grid and were permitted to change them.
Stewards later stripped BJR of teams’ championship points from the race but did not disqualify Percat on the grounds he did not race on the offending tyres.
At the following round Jake Kostecki, Brodie’s cousin who was then driving for Matt Stone Racing, was disqualified from a race after his tyres dipped below the minimum while on the grid.
Supercars is yet to comment on its intention to appeal the stewards’ decision, while Grove Racing said it is surprised to hear of Supercars’ actions.
Grove stunned by Supercars’ intent to appeal Allen non-penalty