The newest Mattel Pixar Cars track sets (2023+) use a redesigned road connector piece. The new design has smaller connectors (which are easier to connector/disconnect) and all road pieces have attach points on the sides to connect buildings and other accessories.
This model should be compatible with these new track sets. Made by me, based on measurements I've taken from track sets that we own. Included is the 3mf/STL for both the longer road pieces (that you can connect to both existing track and buildings/accessories) as well as the smaller 4-sided connectors to turn corners and/or attach additional play sets.
I print these bottom-side-down with slim tree supports enabled. You can see some of the bridging on the under-side of the model but it doesn't compromise the strength or functionality.
enjoy!
The author marked this model as their own original creation.