One of the trends in development of mechanical engineering is that there is an inreasing load capacity of machines. For aerospace industry it is desirable to implement this increase without growing mass of an aircraft, which consists of aggregates, mechanisms, units and machine parts. Among the mechanisms, those that convert rotational motion into translational one account for a sizable proportion. The most promising of them are planetary roller screw mechanisms (PRSM). To increase the load capacity of the PRSM with the same mass is possible due to decreasing α angle of the turn profile of the threaded parts for these mechanisms (see the earlier published paper).The PRSMs have a number of features, one of which is the inequality of the helix angles of the screw and the roller in the contact area, because of which it is necessary to increase the inter-axial distance by increment value. In traditional PRSMs α=90º, and for them, as for a particular case with α=90º, the techniques to determine Δαw have been developed.For the general case, when α angle value is arbitrary (α<90° for increasing the load capacity), a technique to determine Δαw increment (see the second paper earlier published) and a technique for calculating dimensions of the PRSM main parts and their tolerance bands have been developed (see the third paper earlier published), in which Δαw increment is used. Hence, this increment is a key parameter. To determine Δαw a numerical method and a computer calculation program have been developed.This paper presents numerous results of Δαw increment computer calculation according to the developed technique. The Δαw increment value calculated by the developed technique has coincided with Δαw increment value, which was determined for traditional PRSM with the angle α=90º.The paper analyses an effect of various structural parameters on Δαw increment value. It has been found that the radius by which a profile of the roller turns is circumscribed essentially has no effect on Δαw value.The α angle of the profile of turns and the thread pitch of the PRSM parts significantly affect the Δαw value. The paper presents the graphs constructed to determine the coordinates of the point of initial contact of the mating thread turns of the screw and the rollers as well as the graphs to determine the distance from the point of initial contact to the edge of the turn of the screw and the roller. All the information presented can be used to design the PRSMs, including those with increased load capacity.