Injection molding of rubber compounds is a widely used method for manufacturing different rubber products, from consumer parts to seals for harsh environments. Yet its cycle time is tremendously higher than in injection molding of thermoplastics, as rubbers need several minutes of curing. Increasing the mold temperature would shorten the curing time, however, this leads to a premature start of the curing reaction which may cause severe quality and manufacturing problems. To avoid premature curing and to reduce filling problems, Rapid Heat Cycle Molding (RHCM) may be used to first, cool the mold in injection phase (until the cavity is filled) and second, to raise the mold temperature above what would be possible in isothermal conditions. In this study, this approach is evaluated. Employing design of experiments and injection molding simulation, the 3D transient temperature distribution in the mold is investigated. Injection molding experiments were conducted to determine the curing degree as a function of the temperature distribution at the cavity wall. Moreover, simulation accuracy was assessed. To summarize, RHCM can provide a way to achieve the desired degree of cure with higher temperatures than possible using standard temperature control.