Air Cooled Casting Imperfections

[Charles Wilson]

Esp. to RN-I've noticed in several pictures of the air-cooled engines, including the "Display Engine" that made the rounds in the late 70s, that the Side Housings hit the production line very tight, very angular. The Rotor Housings, however showed some variations in the finning, as if the aluminum didn't quite flow all the way out to the periphery when cast. Were there any quality control issues when the air cooled Rotary began production?Thank you,CW