Engine Mount Physics

Added a new Engine Mount Compliance system.

- Simulates engine mount softness and engine torque reaction through the chassis.

- The engine is no longer perfectly rigid — it can slightly load, twist and return through the mounts.

- The engine block pushes into the mounts under load, and the chassis reacts through that elastic connection.

- New value: `engine_mounts_softness`

`0` = fully disabled, zero extra forces.

`1–3` = stiff/race mounts.

`4–6` = street/performance mounts.

`7–10` = soft mounts with stronger engine rock.

• Adds throttle on/off torque kick and a small delayed aftershock.

• Distributes torque across X/Y/Z depending on engine position and layout.

• Supports longitudinal and transverse engines.

• Most noticeable during throttle blips, lift-off, gear shifts and corner exits.

• Result: more mechanical, alive and less sterile car behaviour.

Assetto Corsa - Ecu Tuner #172 - Engine Mount Physics (YouTube)