Pneumatic brake actuator chamber with rotationally positionable housing

A rotationally adjustable brake actuator includes a pressure housing with a circumferential rim, a non-pressure housing having a second circumferential rim, and a diaphragm disposed therebetween, where a retaining ring holds the respective housings against each other such that the first rim abuts the second rim, but where the respective housings are able to be rotated with respect to the other. Further, the retaining ring includes a radially-oriented hole and a stop pin that is inserted into the hole and engages the pressure housing to prevent further rotation.