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This study compares the role of the in-cylinder flow field for spray-guided stratified-charge combustion and for traditional well-mixed stoichiometric operation, both using E70 fuel. The in-cylinder flow field is altered by changing the engine speed between 1000 and 2000 rpm. The stratified operation with the ethanol blend enabled “head ignition” of the fuel sprays, thus minimizing the available fuel/air-mixing time prior to combustion, creating a highly stratified combustion event. For well-mixed stoichiometric operation, the heat-release rate (HRR) scales proportionally with engine speed due to increased in-cylinder turbulence, as is well-known from literature. In contrast, increasing the engine speed influences the stratified combustion process very differently. Ensemble-averaged over 500 cycles, the time-based HRR in kW remains comparatively unchanged as the engine speed increases. However, cyclic variability of the stratified combustion increases substantially with engine speed.