High cycle fatigue (HCF) in a turbine wheel of a sector-divided dual volute turbocharger, particularly a turbocharger where the tongue-to-blade gap is as small as from 1-3% of the wheel diameter, is reduced, by locally increasing the volute cross-sectional area just upstream of the tongues. Thereby, it becomes possible to reduce the force function of the exhaust gas pressure onto the turbine wheel blades. Modifying how the pressure presents itself to the wheel reduces blade excitation and, ultimately, HCF of turbine wheels. In another aspect of the invention, the angle of the tongues are modified to direct the exhaust more directly onto the turbine wheel than conventional tongues. It is surprising that this approach not only accomplishes the desired result, but does this without significant loss of turbine stage efficiency.