Faster Physics

My Situation:
I have created a Physics based game, and now want to train a neural Network to play it.
As I don’t want to train it in real time, I want the training to be as fast as possible. What I think I Need to do is A) disconnect all the rendering etc. from the Physics, and disable them during Training (for performance) and speed up the Physics simulation.
How do I do that?
I don’t find a way to get around the Physics on Rigidbody only being calculated once per Frame, and I use Time.deltaTime in a few places like Manual movement.

You can try to turn off Physics.autoSimulate and call Physics.Simulate() youself.