Some of the Repco Supercars Championship’s most credentialled drivers will test the category’s Gen3 prototypes at Symmons Plains today and tomorrow.

The new-look Ford Mustang and all-new Chevrolet Camaro made a cameo appearance at the Ned Whisky Tasmania SuperSprint last weekend, marking the first passenger laps for either car.

Symmons Plains International Raceway is only the third circuit the Gen3 cars have appeared after Queensland Raceway and Mount Panorama, the latter where the cars debuted last year.

Today, the first of two days of prototype testing will take place.

On Day 1, the Mustang will be driven by Tickford Racing’s Cameron Waters and James Courtney while Grove Racing pair Lee Holdsworth and David Reynolds will test on Day 2.

All but Courtney in that quartet have not previously driven the Gen3-spec Mustang.

Meanwhile, the Camaro will be driven by 2007 champion Garth Tander and 2015 champion Mark Winterbottom today.

Two-time champion Shane van Gisbergen is also set to test today after an initial taste of the newly configured cockpit on Friday prior to the Tasmania SuperSprint.

The Red Bull Ampol Racing driver was vocal in calls for ergonomics to be adjusted and the manual sequential shifter be installed, getting his wish in both instances.

Brad Jones Racing’s young guns Bryce Fullwood and Jack Smith will drive the Camaro on Tuesday.

The Symmons Plains test will see the category take another step closer to the racing rollout of the cars next year.

The heavy braking loads of the short seven-turn circuit are of particular interest for Supercars this week, putting the AP Racing brake package to the test ahead of its specification being finalised.

Courtney, who drove the Mustang at Mount Panorama and Queensland Raceway, said he’s keen to see if the ergonomic changes have made a difference.

“It’ll be good to see the progression – and hopefully the changes, it sounds like, are heading in the right direction,” Courtney told Speedcafe.com.

“It should be interesting. It still hasn’t got any roll bars or anything. I think we’re just testing brake packages and trying to lock down what that’s going to be.

“I was pushing for it to be changed. I haven’t got in it yet, we’ve had so much on this weekend.

“Hopefully that’s all fixed up because it’s going to be a nightmare; one, for the big guys, and two for the longer races with cramping.

“Ergonomically, if they’ve fixed that, it’ll be good. Hopefully we can lock in a braking package.”

The 2010 champion admitted he was unhappy with the feel of the car after his first drive of the car, but conceded that should be expected with the baseline set-up.

Both cars are running without anti-roll bars after a failure during the recent Camaro shakedown at Queensland Raceway. Although the anti-roll bars on the Mustang are intact, Supercars has opted to run both cars in identical configurations.

“It feels pretty crap at the moment, to be honest, the way it is just because it’s got no set-up,” Courtney explained.

“It’s a base set-up. Nothing is set. They don’t want anyone to get a feel for speed.

“You won’t get any feel as to what it’s actually like to race until the teams get them and they start to change things. I’m sure it’ll be fine.”

Team 18’s Winterbottom said he’s eager to have his second run in the Camaro and see how the car has progressed since driving the car at Mount Panorama last December.

“I got to drive it obviously at Bathurst when it had a few differences,” said Winterbottom.

“It’ll be nice to drive it. I’ve been watching it all weekend with Marcos [Ambrose] and Garth [Tander] going around.

“It’ll be good to have a genuine back-to-back with two days racing. Hopefully it’s getting closer to where it needs to be.

“I look at it from the sport point of view. I don’t have any hidden agenda. I’ll give feedback on things I think are good and not good.

“After racing for 18 years you kind of have an idea of what works. If you can give your input it just makes the sport better, which is better for everyone.”

After the Symmons Plains test, the Gen3 prototypes are set to go on display at the Formula 1 Australian Grand Prix with testing to continue at Phillip Island in the days after.