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model_heading = prev_speed * dT / R = 2 * prev_speed * tan(c*prev_steer) * dT / (w * sqrt(4 * tan^2(c*prev_steer)))
Where R is the curvature radius obtained from the model described in section STEER INPUT - CURVATURE RADIUS RELATIONSHIP, c is the steer factor and w is the wheelbase of the car. This is the current heading according to the model.
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