I remember reading 5 or 6 yrs ago when Toyota was entering the truck series (I think) they had to find people & equipment for making cast iron blocks again. Having to relearn old technology just doesn't make sense, especially for a company that is also in F1.
NASCAR could be interesting if the cars actually were V6, FWD, 4 doors with a cage and engine mods, suspension, & brake upgrades. Instead of cookie cutter pushrod V8s w/ RWD & a tube frame. And big penalties for making unclean passes & contact. Make things closer to what the stock car is and allow some innovation, not cookie cutter clones driven by rednecks who can't turn right and refuse to drive cleanly.