The effects of temperature, pressure and flow on relaxation times, nucleation density, spherulitic growth rate, as well as the interrelation among these quantities and the distributions of deformation rate and cooling time during the process, determine the morphology distribution in the final polymeric part. Each of the effects mentioned above was experimentally analyzed and described by a model for the iPP grade considered in this work. The combination of all these specific models becomes a model for the morphology evolution during polymer processing and its application to the injection molding process was numerically developed into the UNISA code. Injection molded samples were obtained with a fast evolution of cavity surface temperatures technique allowing to keep, for assigned time intervals, the cavity surface temperature at intermediate values between injection and cooling channels temperatures. A modulation of the level of the cavity surface temperature and of the time, it was kept active, allowed to control the final sample morphology all the way from the complexity of a standard injection molded part down to a completely (skin and shear layers free) spherulitic structure. The fibrillar layer morphology was related to the achievement of critical values of the molecular stretch and of the mechanical work, the latter being performed after the achievement of the critical molecular stretch. The dependence of the morphological layers (skin, shear, spherulitic layers) thicknesses and the spherulite diameter distributions (inside the corresponding layers) were satisfactorily described by the models adopted.