I have 3D printed 7 cars and 4 of them are built and running hot laps. The 3D printed parts are holding up very well.
My tire design is printed in TPU and capped with EPDM rubber and is working very well on concrete.
I have just printed the front rim and tire as one unit in PETG and capped that with the EPDM rubber and it seams to work just fine.
The PETG rim/tire is being tested on car #4. Hot laps of that car are coming soon.
Here is video of hot laps of car #1 with onboard video.