A variable compression connecting rod system (10) located in an internal combustion engine (12) and a method of assembly can include a connecting rod (28) mountable to a piston pin (26) having a first longitudinal axis at one end and 5 mountable to a crankpin (22) having a second longitudinal axis at a second end portion (36). A hydraulically actuated eccentric rotor (52) rotatable about one of the first and second longitudinal axis. The eccentric rotor (52) including first and second vanes (54a, 54b) for driving the rotor between first and second angular positions in response to fluid pressure acting on the first and second vanes. The eccentric rotor 10 (52) having an eccentric surface area with different radial distances (80, 82) movable into alignment with a longitudinal axis of the connecting rod (28) for varying a longitudinal length of the connecting rod (28) between the first and second longitudinal axis.