Valve system for a gas turbine engine

A valve system (30) intermediate a secondary flow path and a primary flow path selectively communicates secondary airflow into the primary gas flow path and controls airflow injected from a higher pressure plenum into a lower pressure flowpath. The system includes a valve seat (34) and a valve member (32) rotatable relative to said valve seat (34) between an open position and a closed position, said valve member (32) defining a cylindrical surface (36) which defines said closed position and a sculpted surface (38).