The effects of injection-molding parameters on the mechanical-physical properties of a liquid silicone rubber (LSR) injection-molded ring were studied through an experimental design. The effects of the changeover point (volume or pressure driven), runner (hot or cold), hold pressure, mold temperature and injection flow rate variations were evaluated based upon the responses related to both material properties (ultimate elongation and tensile stress in a tensile test, swelling in hexane, hardness, density) and ring properties (cross sectional diameter, weight, volume). It was determined that ring density is not dependent on the parameters studied. The mold temperature appeared to be a very influential parameter, especially concerning material characteristics: it affects the swelling ratio, hardness, and ultimate properties, but weight and volume are only affected when the cold runner is used. The hold pressure has an effect on both the weight and volume of the ring. The type of changeover used (volume or pressure) has no effect when a cold runner is used, but affects the weight, volume, and ultimate properties of the ring, when a hot runner is used. The injection flow rate did not affect the observed characteristics.