The last stage of classical transport modelling, known as the sequential model of the four steps, estimates the flow pattern of the system. Then, in a post-processing phase all measures of system performance such as the level of service and externalities are estimated. This paper compares the estimated BPR and conical volume-delay with data taken in six multilane roads in Bogota, finding ranges of recommended function parameters values. We concluded that the values traditionally used for these functions are not the best for explaining the congestion that occurs in the environment studied.