Supercars has pushed the introduction of its Gen3 technical package back to 2022.
Having originally been slated for 2021, the new rules have been delayed as the category continues to tinker with the existing package.
Former Bathurst 12 Hour event director John Casey, meanwhile, has been charged with the task of developing a market-relevant set of Gen3 rules in a new Head of Strategy and Products role, which will be rolled out in 2022.
That will put the new regulations in line with Holden's new two-year commitment, the brand having already confirmed it wants to continue with the four-door Commodore for at least the life of that deal.
"[Casey is] leading the process," said Supercars CEO Sean Seamer.
"He's meeting with homologation teams, he's meeting with manufacturers, he's consolidating an update of where we think the market's going to, and what we think we need to achieve maximum market relevance.
"And that's the number one priority. Market relevance, is the key piece, and it will be engineering-delivered, not the other way around.
"It's still early days in the work that John's been doing. Some of the stuff that we were looking at that we wanted to get done, we've fast-tracked for next year around tyres, around internal electrical systems, the dorian, the LED panels, all of those things. We've fast-tracked the potential introduction of a control damper.
"As we always said, if a good idea came up, we weren't going to wait.
"The reality on timing now is that if there were to be a new car or a re-design of a car, by the time you get that done, you get that tested et cetera, 2022 is the most likely scenario."
However specific detail of the chassis is not something Seamer will be drawn on right now, his focus instead on reading an evolving automotive market.
"The hardest part is, what cars are going to be sold in 2022?" he said. "And how much longer will those cars be sold for beyond 2022?
"Therefore, what underlying package do we need to be able to run those cars and have maximum market relevance?
"Are we going to throw everything in the bin that's out there now? Absolutely not. Do we need to change it to adapt to that level of market relevance? Yes."
As for hybrid power trains, Seamer added: "We will assess hybrid as part of that. Just as NASCAR and the British Touring Car Championship have."
One thing Seamer says the series will retain is its "fast and loud" approach to motor racing, leaving full electrification or significant drops in horsepower as unlikely outcomes.
"Fast and loud," he said. "I think IndyCar's done a really good job of sticking to that, and I think a big part of why they've had recent success is that the entertainment factor's important – and we acknowledge that."
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