I have a question for you Scawen, i wonder why the physics in fz50 ingame is different to the lfseditor version?
I tried to export the fz50 with no changes done from LFSE to LFS and the ride height is different and it handles differently.
PS it's the same custom setup on both cars. Even on default its different

This post seems related:
https://www.lfs.net/forum/post/2076305#post2076305

Quote :

...these development models have the model object centre correctly located at the lowest point of the model, instead of at rough ground level or whatever other random position they were in the old versions.

It's not because of the location of the object centre. That doesn't affect physics, but it does mean the setups are not interchangeable.

The editor cars have been updated to have realistic setups. I don't know the specifics, but maybe you could open two instances of LFS and look through side by side, to see what the changes are. That's the only way I would be able to tell you the changes.

If you replicated all the settings and confirm the wheel sizes have not changed then you should get the same handling. It's likely that rim width has decreased because most of the public LFS ones are unrealistic (long subject, watch the video if interested). But rim with in LFS doesn't affect much, probably just affects wheel heating a tiny amount over a long period.

Differences between current public version and versions set up for future release aren't something I will get involved in or take an interest in.