I really liked the Tokyo Xtreme racer games. They are still probably the best car RPG games. I would love to see what someone could do now in the same vein. Even tokyo xtreme never got quite as crunchy or difficult as I would have liked.
I want to go so far as to be like a tactical survival style game, where you are out there earning a living wage from daily(nightly) car racing, and putting most of it back into your car. Just the repairs and maintenance alone being a bar you have to meet and beat every day on average to stay afloat, and then you can think about upgrades after.
It basically takes an environment like that for it to matter in a racing game that there are upgrades between the worst and the best. If trying to save up for even one good part wouldn’t be possible without at least some middle parts first.
Meanwhile, could have some “roguelite” elements too in driver experience/skill. The car is only half of what’s winning the races afterall. And even if you really blow it at some point and your car is fucked and you need to salvage and pull together what you got and go back to a cheaper car to maintain/repair, you’ll still have all the experience/skill your character personally gained helping it go a little smoother this time.