Ford is “prepared to react” in the event that there proves a disparity between the Mustang and Chevrolet Camaro Supercars this weekend, but is keeping an open mind.

The Thrifty Newcastle 500 gets underway with opening practice tomorrow morning after Supercars announced formal homologation of the race cars just 24 hours ago, off the back of parity testing at Temora last week.

From that activity, the Camaro was given a small increase in front downforce by way of a wheel arch extension, while a new engine calibration was verified for the Mustang.

Homologation necessarily means that all parties are operating on the basis that technical parity has been achieved but, with changes being made at the last-minute, there cannot be certainty at least until cars hit the race track in anger.

Speaking today in Newcastle’s pit lane, Ford Performance’s Global Director of Motorsports, Mark Rushbrook, expressed full confidence on aerodynamics, but implied he is less comfortable about powertrains.

“I think [there is] very clear aero parity,” he told assembled media.

“On the powertrain side – engine [and] acceleration – we knew at the beginning that, with different engine architectures, it was going to be a challenge, right?

“Instead of two engines – pushrod engine, same displacement – they have different displacements and different technology.

“You can always meet on a dyno when you look at a watt run, but how they perform in the car can be different.

“So while there is equivalence, certainly, on the dyno, that manifests itself differently in the car.

“So, some adjustments have been made within the calibrations that are in the cars to account for that, and we’ll see how it works this weekend.

“But, I think everyone is going into it with the right mindset, that we’ll see how it works this weekend, and certainly if further adjustments need to be made, then they can be.

“There’s a process for that which will be driven through data, and transparent and collaborative.”

When asked by Speedcafe.com what that process entails, Rushbrook replied, “Well, I think it depends on what we see, partly.

“But the good thing is, people are going to be looking at that data this weekend, through the weekend, and we’ll be prepared to react.”

There has been dissatisfaction with how the Mustang changes gears relative to the Camaro, with the latter given an elongated shift cut at the official pre-season test at Sydney Motorsport Park which remains.

It was in Sydney that Mustangs were hamstrung by a new engine map, but the version run at Temora Aerodrome and then in private testing at Winton last week was met far more positively and will be used this weekend.

While cautious on whether or not powertrain parity has been achieved, Rushbrook is also not expecting per se that there will be a difference.

“Not necessarily,” he stated.

“We need to realise, right, we haven’t had this many of these many cars running on the track at the same time, and under true practice, qualifying, and race conditions.

“We’ve seen that in so many other series that we’ve been in – and so has everybody else in this sport – that every time you put a new car on the track, you learn something from it.

“So, I think the proper effort certainly has been put forward with the right spirit from everybody involved, and we think we’re in a good place coming into the race this weekend.

“But, we don’t know what we don’t know, and as we get more data, we’ll see what it says.”