A multi-part rubber compound comprising: (1) a first compound comprising an elastomer (1)(a) and a vulcanizing agent, and having a ts2 of at least 1.5 minutes; (2) a second compound comprising an elastomer (2)(a) and a cure accelerator, and having a ts2 of at least 1.5 minutes; and (3) one or more optional compound comprising an elastomer (3)(a) and having a ts2 of at least 1.5 minutes; wherein: at least one of (1)(a), (2)(a) and (3)(a) has a Mooney viscosity of 20-75 measured at 100° C. (ASTM D1646), the first, second and optional compounds are kept separate until the multi-part compound is used, a blend of equal volumes of the first and second compounds, optionally with an equal volume of the optional compound, has a ts2 of less than 0.7 minutes, ts2 being measured at 190° C. (ASTM D2084), and a process for blending, injection molding and curing a rubber compound by injecting combined streams of rubber compounds from an injection chamber at a pressure of at least 10,000 psi into a motionless mixer provided downstream.