Abstract: An automatic control valve system for a multiple ratio power transmission mechanism for an automotive vehicle wherein the mechanism comprises multiple gear elements, the motion of which is controlled by selectively engageable clutches and brakes, a pressure source driven by a power input element of the transmission, a valve circuit for distributing pressure from said source to the clutches and brakes to establish a shift sequence, a pressure regulator valve that is responsive to engine intake manifold pressure and to speed whereby an increase in engine throttle setting will result in an increase in circuit pressure in the control valve system, and a throttle pressure cut-out valve that interrupts distribution of engine intake manifold pressure signals to the pressure regulator valve during operation of the mechanism in the highest speed range thereby preventing an excessive pressure in the control valve system while retaining an adequate residual pressure to maintain clutch and brake engagement during high sp