Mark Winterbottom believes the Gen3-spec Chevrolet Camaro prototype has come a long way since he last drove it late last year.

The Team 18 pilot was among the first few drivers to sample the Triple Eight Race Engineering-built prototype around Mount Panorama at the 2021 Bathurst 1000.

In the four months between outings, the Chevrolet Camaro and Ford Mustang have undergone several changes to aid driveability and comfort.

Earlier this weekend Supercars continued prototype testing at Symmons Plains in the days after the Tasmania SuperSprint.

Winterbottom was among the drivers to sample the Camaro, alongside Shane van Gisbergen, Garth Tander, Bryce Fullwood, and Jack Smith.

The Mustang, built collaboratively by PACE Innovations and Dick Johnson Racing, was driven by Cameron Waters, James Courtney, Lee Holdsworth, and David Reynolds.

Although the car Winterbottom drove at Symmons Plains earlier this week ran without anti-roll bars, he said Supercars has made significant strides forward since the start of December.

“It’s a big difference, but a big difference in a good way,” Winterbottom told Speedcafe.com.

“I think it’s come a long way. It’s fun to drive. I think the car physically, and how it makes you work and hustle, is pretty cool actually.

“Pretty impressed. I think it’s a lot further down the track than where I thought it potentially was, which is good as well.

“The horsepower is really good. No vibrations, no [brake] knock-off, none of those things that can bring you undone with a new car.

“The sport will be a lot better with these cars because you have to drive them and I think having control bits and all that sort of stuff, it’s so exciting.

“I was pretty happy to come away from the test kind of pretty impressed with where it’s at.”

The most noticeable shift that Winterbottom has noticed between Gen2 and Gen3 is that away from generating aerodynamic grip.

It’s widely accepted that the Gen2 cars have grown too dependent on downforce to generate grip in recent years.

With Gen3, that will no longer be the case. Gone is the extended floor beneath the front splitter, while the rear wing is largely a cosmetic piece with far less aerodynamic capacity.

With a greater focus on mechanical grip and the lack of downforce, Winterbottom said the car is a lot more enjoyable to drive – something van Gisbergen also noted this week.

“The car moves around,” he said.

“And the best way to have tyre deg is have a car that moves around a bit and has a shitload of power when you put your foot on the throttle.

“We can make all these compounds and all this sort of stuff that we do – every year there seems to be a different tyre – but if you just make the car use the tyre, then you end up with deg.

“I did a 22-lap run and by the end of it, you’re working pretty hard, trying to hold on and things sliding.

“It’s got a heap of horsepower and wheel spinning out of the corner. I was pretty impressed by that I thought. The racing should be pretty strong when you put 25 of them together.

“I think the racing will be a lot better.”

Winterbottom said he’s interested to see how the cars fare once they are aero tested, although he expects there’ll be little between them.

As far as outright pace goes, he believes the cars are like-for-like at the moment, and what he saw on track validated that.

Testing is set to resume at the Phillip Island Grand Prix Circuit after the Beaurepaires Melbourne 400 at the Formula 1 Heineken Australian Grand Prix on April 7-10.