Vehicle Physics Fails if u got more then 3 cars on track

It is a Bug or not i dont know :wink:

How can I improve my physics bots ? As soon as I have more than 3 cars on the track , failed physics calculation . The cars sometimes remain stuck in the ground . It looks like the physics would be calculated too late. I 've played with the Substepping but brought only limited improvement.!

It is very strange that everything is fine as long as I only have 3 cars on the track
I would appreciate any ideas .

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U can see the Fail in this video
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Regards
Christopher

Apologies for the delay.

If you’ve already tried using sub-stepping and only seen minimal improvement, would you be willing to share the project or a sample project that has the same issue since it’s got a lot of setup that would not be easily reproducible for me?