An electric phaser for dynamically adjusting a rotational relationship of a camshaft with respect to an engine crankshaft of an internal combustion engine includes an electric motor and a tapered roller drive. The tapered roller drive includes a sun, rollers, a carrier, at least one ring, and at least one load generator providing an axial load. The rollers are maintained in rolling engagement with the sun and the ring without the use of teeth. In some embodiments, the tapered roller drive is based on a fixed-sun design. In other embodiments, the tapered roller drive is based on a split ring design.