Patent ID: 7287444

Claim:
A kit for modifying an automatic transmission, the transmission including an input shaft and a positive displacement pump providing fluid flow substantially proportional to the rotation of the input shaft, the transmission further including a reservoir of fluid accessible to the pump, the transmission further including a modulation circuit and a modulation pressure regulating solenoid controllable by an automotive computer, the transmission further including an exhaust port whereby excess fluid from the modulation circuit may be exhausted into the reservoir, said kit comprising: an orificed check valve including a spring fitting configured to receive a compression spring, said valve including a seating portion configured to provide a seal against the seat of the exhaust port of the modulation pressure circuit under condition of compression force applied to the spring fitting, said check valve further including a passage through said check valve forming an orifice, wherein said orifice includes an inlet positioned in said seating portion to receive pressure from fluid maintained in the modulation pressure circuit, further wherein said orifice includes an outlet whereby fluid passing through said orifice may be returned to the reservoir, and wherein the orifice has a sized opening sufficient to maintain a substantially linear relationship between fluid flow produced by the transmission pump and the pressure developed in the modulation pressure circuit such that higher pressures are delivered in the line circuit with increased fluid flow into the modulation pressure circuit and through said orifice; a substitutionary component for the modulation pressure regulating solenoid, said substitutionary component having similar characteristics to the regulating solenoid as sensed by the automotive computer.