In part 1 of this paper a qualitative analytical method to predict the preferred gas flow direction in gasassisted injection molding (GAIM), which involves flow through panel-areas of various fan-shaped geometries, and the criteria to apply the method were presented with appropriate assumptions. Then the definition of a resistance to initial velocity was proposed as a rule of thumb, by which the gas directions of GAIM were predicted under various fan-shaped geometries. Upon performing the simulation on them with commercial software (MOLDFLOW), we compared the ratio of simulated gas penetration lengths to both directions with the predicted ratio of resistances as well as the predicted direction of the gas flow in GAIM using the suggested rule of thumb herein presented. The predictions with the suggested rule of thumb were generally quite consistent with the results of simulation (MOLDFLOW). However the discrepancy between the ratio of gas penetration lengths and the ratio of resistances was observed to increase as the ratio more{(H/R₀)(one-side)/less(H/R₀)(the other-side)}of the values of H/R₀ on both sides of fan-shaped cavities became bigger even though the suggested rule of thumb was assumed adequate to use until the case met the condition of (H/R₀)² 1/θ² << 1 and (H/R₀)² << 1. Nevertheless, the suggested rule of thumb was still effective as far as the direction of gas flow was concerned.