Variable turbine nozzle and valve

An air cycle machine (12) includes a turbine wheel (34), a turbine inlet nozzle (32), a valve body (52), and a poppet member (40). The turbine wheel is mounted to rotate within the air cycle machine and the turbine inlet nozzle is positioned to direct airflow thereto. The poppet member selectively extends into the turbine inlet nozzle and the valve body controls a pressure on the poppet member to move the poppet member relative to the turbine inlet nozzle to vary the size of the turbine nozzle directing airflow to the turbine wheel.