An injection molding system is disclosed that utilizes a melt channel wherein at least a portion of the melt channel has a noncircular cross-section for balancing shear in a melt stream of moldable material that flows therethrough. The noncircular cross-section of the melt channel portion may be, for e.g., capsule-shaped, extended egg-shaped, oval, teardrop-shaped, or peanut-shaped. A flow splitter is also disclosed that is positioned offset from a central axis of an upstream melt channel to protrude between inlets of respective downstream melt channels, where the upstream melt channel splits into the downstream melt channels, to thereby create a narrower inlet into one of the downstream melt channels and a wider inlet into the other of the downstream melt channels.