The Stirling cycle engine module is a conventional single cylinder, twin-piston displacer-type engine, with the addition of a rotary valve/crankdisc which times and isolates the thermal phases of the cycle, so that effective thermal separation is maintained for maximum operating effectiveness. Multiple hot and cold conduction threaded rods are uniformly placed within the respective displacer zones for more effective heat transfer. A modular system is adopted of ganging individual engine modules into a custom power package, to suit various applications. Each module is secured in a cradle frame with each fly wheel drive gear meshing with pinions on a common drive shaft extension. An evaporative cooling arrangement is included for more effective heat sinking and reduced cooling surface area. A "v" engine module type is described which features thermal isolation techniques as an alternate engine modular system.