Dear god, ever since Mazda split with Ford on chassis and parts (around the same time their cars got lighter, quicker, more fun to drive and more reliable too), I've hoped. It's not likely, but as a long time Mazda fan/owner, I want nothing more than to see a MazdaSpeed 6 compete.
Honda is probably the safest bet, as that's been booted around the rumor mill for what? A decade now?
I faintly recall reading something about Nissan being in slight trouble financially, although it's allied partner Renault could help there, if they weren't both bailing out the last 3rd of their trifecta, Mitsubishi.
I think people are overlooking BMW though. BIG plant in South Carolina. A borderline cult following. 550 hp would be easily doable for them.
I know this had been beaten into oblivion, but Dodge. There was another merger involving Fiat Chrysler Motors, and Peugeot, thus creating Stellantis, which holds brands from Fiat Chrysler, Peugeot, as well as Alfa Romeo, Maserati, Opel and Vauxhall. All names associated with racing/performance. Don't count them out just yet.
I would say Audi, but parent company Volkswagen has enough trouble to deal with. They have the resources, sure, but I believe their focus is elsewhere, and a 550 hp engine is
not going to entice them, when they were plenty capable of entering with a MUCH higher hp level. Remember, parent company of Bugatti and Lamborghini. HP is NOT an issue lol
I think it's been stated before that what makes things difficult is actually breaking into NASCAR, especially with the charter system, and now even more so with charters being held by prominent/solid teams next year. They would need a team to convert over.
Hendrick has a solid relationship with Honda, but him ditching Chevy is as likely as Mark Martin coming out of retirement.... again...
JGR isn't budging from Toyota as they have a nice stranglehold on manufacturer support.
Roush is Ford. I don't think there's a 'Roush' tuned anything other than a Ford.
I think teams like Childress (and thereby RPM), Trackhouse, DTG, even SHR (if the price is right, Gene and Stewart are businessmen to the core), and DEFINITELY Penske if Ford doesn't maintain it's support, are potential candidates for a swap. More so if Chevy's recent surge wanes enough, the teams here that run that manufacturer don't have the resources or staying power of HMS, might look for backing from an alternate OEM.