The invention contemplates an improved ported cylinder construction and method wherein the precision of die-casting is used in the separate construction of a cylinder body and of a cylinder liner wherein ports and grooves are so formed in these parts as to cooperatively define inlet and exhaust passages, upon correctly registered assembly of the ports. In the specific form disclosed, the assembled cylinder provides for side-ported exhaust and an array of inlet-mixture passages for communicating a crankcase-compressed combustible charge to liner-bore regions selected for best scavenging of exhaust products.