Optimizing the inter-distances between vehicles is very important to reduce traffic congestion on highways. Variable spacing and constant spacing are the two policies for the longitudinal control of platoon. Variable spacing doesn't require a lot of data (position, speed...) from other vehicles, and string stability using only on-board information is obtained. However, inter-vehicle distances are very large, and hence traffic density is low. Constant spacing can offer string stability with high traffic density, but it requires at least data from the leader. In [1], we have proposed a modification of the constant time headway control law. This modification leads to inter-vehicle distances that are close to those obtained with constant spacing policies, while requiring only low rate information from the leader. In this paper, the work done in [1] is extended by taking into account the model of the motor. This enables to reduce the distance between the vehicles to 1 meter, and it has been proved that the platoon is stable and safe in normal working mode. Simulation results are done using TORCS simulator environment.