Drive train output can be positive or negative, based on whether the engine is accelerating or decelerating. Braking output always opposes the rotational velocity of the tire. Ambient Temperature is the outside air temperature. Ambient temperature has an effect on the operating temperature of the tires, which also effects the tire pressure, grip and tread life. Since air temperature does not vary drastically, this variable can best be modified through a separate method.
Delta t is the length of the time slice.
This is used to integrate tread wear and temperature effects. Since this will typically not vary during a race, this variable can best be modified through a separate method. The Force Vector returns the force to be applied to the car as a result of the various inputs. The Steering Torque is the amount of force returned through the steering wheel to the driver for this tire.