An arrangement of a gas turbine engine and an air turbine starter system, wherein the gas turbine engine includes a core that includes a compressor and a turbine, wherein the air turbine starter system comprises: a compressed air source providing a first portion of compressed air and a second portion of compressed air; and an air turbine starter mechanically connected through a gear assembly to the engine core, wherein the air turbine starter comprises: a housing; and a rotor arranged in a rotor cavity of the housing; wherein the housing comprises: a first manifold having a cavity with a port operative to direct the first portion of compressed air to the rotor, for rotation in a first direction; and a second manifold having a cavity with a port operative to direct the second portion of compressed air to the rotor for rotation in the first direction, and wherein: the first manifold is larger than the second manifold; the air turbine starter is communicatively connected to the compressed air source; the first manifold is connected in parallel with the second manifold between the rotor and the compressed air source; and the rotor is mechanically linked through the gear assembly to the core of the gas turbine engine such that rotation of the rotor rotates the compressor and the turbine of the gas turbine engine. a compressed air source providing a first portion of compressed air and a second portion of compressed air; and an air turbine starter mechanically connected through a gear assembly to the engine core, wherein the air turbine starter comprises: a housing; and a rotor arranged in a rotor cavity of the housing; wherein the housing comprises: a first manifold having a cavity with a port operative to direct the first portion of compressed air to the rotor, for rotation in a first direction; and a second manifold having a cavity with a port operative to direct the second portion of compressed air to the rotor for rotation in the first direction, and wherein: the first manifold is larger than the second manifold; the air turbine starter is communicatively connected to the compressed air source; the first manifold is connected in parallel with the second manifold between the rotor and the compressed air source; and the rotor is mechanically linked through the gear assembly to the core of the gas turbine engine such that rotation of the rotor rotates the compressor and the turbine of the gas turbine engine. a housing; and a rotor arranged in a rotor cavity of the housing; wherein the housing comprises: a first manifold having a cavity with a port operative to direct the first portion of compressed air to the rotor, for rotation in a first direction; and a second manifold having a cavity with a port operative to direct the second portion of compressed air to the rotor for rotation in the first direction, and wherein: the first manifold is larger than the second manifold; the air turbine starter is communicatively connected to the compressed air source; the first manifold is connected in parallel with the second manifold between the rotor and the compressed air source; and the rotor is mechanically linked through the gear assembly to the core of the gas turbine engine such that rotation of the rotor rotates the compressor and the turbine of the gas turbine engine. wherein the housing comprises: a first manifold having a cavity with a port operative to direct the first portion of compressed air to the rotor, for rotation in a first direction; and a second manifold having a cavity with a port operative to direct the second portion of compressed air to the rotor for rotation in the first direction, a first manifold having a cavity with a port operative to direct the first portion of compressed air to the rotor, for rotation in a first direction; and a second manifold having a cavity with a port operative to direct the second portion of compressed air to the rotor for rotation in the first direction, and wherein: the first manifold is larger than the second manifold; the air turbine starter is communicatively connected to the compressed air source; the first manifold is connected in parallel with the second manifold between the rotor and the compressed air source; and the rotor is mechanically linked through the gear assembly to the core of the gas turbine engine such that rotation of the rotor rotates the compressor and the turbine of the gas turbine engine. the first manifold is larger than the second manifold; the air turbine starter is communicatively connected to the compressed air source; the first manifold is connected in parallel with the second manifold between the rotor and the compressed air source; and the rotor is mechanically linked through the gear assembly to the core of the gas turbine engine such that rotation of the rotor rotates the compressor and the turbine of the gas turbine engine.