A combustion systems and components for rotary ramjet engines. An injection system, optionally stratified for ease of engine startup, provides an air and fuel mixture to a combustion chamber. An ignition system ignites the mixture. A flameholding system may be positioned for communication with the combustion chamber to force an ignited flow of the air and fuel mixture toward a center of rotation within the ramjet engine. The ramjet engine may have a diverging stator for improved exhaust efficiency. The ignition may take place in the engine air intake. Alternatively, the ignition may take place within the combustion chamber using a dual-hub electrically charged system. An impulse turbine may use recirculation of injected fuel to cool a rim-rotor and/or to reduce windage on the rim-rotor. A sealing system may reduce gas leaks from a fuel conduit into the engine air intake.