is offset from base line 100 by an angle 90a and 90b respectively of approximately 2 5 degrees in the direction of rotation of rotating member 22 for bottom plate 32 the center of exhaust gas manifold openings 94a and 94b is offset from base line 100 by an angle 102a and 102b respectively of approximately 2 5 degree in a direction opposite to the direction of rotation of rotating member 22 in other words openings 82a and 82b in top plate 30 are offset approximate 5 degrees in the direction of rotation of rotating member 22 from openings 94a and 94b respectively in bottom plate 32 this represents the optimum rotational angle for a sonic pressure wave to transit the length of rotating member 22 operating at an optimum rotating speed it must also be noted in fig1 that exhaust gas manifolds 16a and 16b where they are connected to bottom plate 32 are placed at an angle 103 of approximately 75 degrees to the plane of bottom plate 32 and the bottom surface of rotating member 22 in the direction of rotation of rotating member 22 in other words the longitudinal axis of exhaust manifolds 16a and 16b acting as a nozzle where they are connected.