Cameron Waters says it is too early to tell if a new aerodynamic package has turned the Gen3 Mustang Supercar into a better race car.

The Tickford Racing driver was the quickest of the Ford contingent in practice at the NTI Townsville 500, where new bodywork has been introduced to the Mustangs following a parity review.

The suite of changes is intended to correct a loss of downforce when the car pitched under brakes, which is said to have caused the airflow underneath the rear wing to stall.

Today’s two half-hour practice sessions at the Reid Park Street Circuit were thus a live test for all five Ford teams, with Waters ended up third in the field, behind Camaros from Matt Stone Racing and Brad Jones Racing.

“Too early to tell, to be honest,” he said, having finished three tenths off the pace but less than a tenth away from second place, on a 1:13.7641s.

“It’s obviously different, so it’s doing something.

“It’s going to take time to get our head around it and see if it’s a better race car.

“That’s obviously the thing that we’ve been struggling with; tyre life and a race package.

“Quali[fying] speed hasn’t really been our drama as much as race car.”

The changes are the addition of a three-millimetre gurney on the trailing edge of the rear wing, a reduction in maximum rear wing angle to five degrees, a shift of the wing downward 25mm and forward 25mm, and a larger, curved boot spoiler.

The review entailed analysis by Ford homologation team Dick Johnson Racing, CFD work by D2H Advanced Technologies in the United Kingdom, and race track validation.

Waters himself is understood to have had some limited running as part of the review exercise at a damp Winton before DJR’s Will Davison tested the new package at Queensland Raceway.

Like his lead driver, Tickford Team Principal Tim Edwards was also not willing to yet declare the changes a success.

“The reality is, the category is so close,” he told Speedcafe.

“How would you honestly know? Unless you actually did it back-to-back on the same day, you have no means of saying.

“The only people have actually done the back-to-back was obviously DJ’s when they did it at QR last Friday, and from the back-to-back, they feel it was better.

“But for us, you come to a track you haven’t been to for 12 months, that’s got a different grip level to last year, you’re in a different car… There’s absolutely no way of ever saying, ‘Oh, yeah, it’s better for sure.’”

Nevertheless, Edwards has given something of an endorsement of the fix.

“The only person who’s actually felt what both feel like on the same car on the same track on the same day is Wilbur,” he added.

“We’re not going to know if this is a part of a big part of the fix until the race.

“All we can do is put our faith in the fact that they’ve done the CFD testing, they discovered the issue in the CFD testing, and in CFD, they’ve now rectified the issue, so it should be exactly the same as the as the Camaro.”

The discovery does at least tally with Waters’ real-world experience.

“Yeah, hundred percent,” said the 2022 Bathurst 1000 pole-sitter.

“The car’s been very loose; under brakes, we’ve struggled compared to Camaros that I’ve been racing.

“It’s good that Supercars went about it, looking at data and did the data share, and made sure they actually worked out what the issue was, and then put some logic behind it with D2H.

“It was good that they found something, to be honest.

“I was starting to feel like I was going crazy inside the car, I’d just forgotten how to drive to the apex, but it’s good they found something.”

While Waters was third in Practice 2, it was a different story in the first session of the day when he was only 17th, yet still best of the Tickford quartet.

“I think [in] the first session, they drove out and went, ‘Oh, my God, this is so different to what we were driving,’” recalled Edwards.

“What they felt was the balance shift of the aero, and so we’ve had to work hard between the sessions to reset the car mechanically, for the new balance.

“They were more happy but Cam’s still not happy. But, by ‘not happy’, he’s a race driver, they never are; they can be a second in front of second place, and they still wouldn’t be happy.

“So, it’s encouraging that we’ve been able to make some progress in what’s a very short amount of practice; two half-hour sessions.”

Qualifying for Race 16 of the Repco Supercars Championship starts tomorrow at 10:15 local time/AEST.

Additional reporting by Mark Fogarty