The present invention provides a method and system of modifying a torque converter clutch control system having a hydraulic circuit including a solenoid signal line, a torque converter IN line, a torque converter OUT line, a lockup clutch apply line, and a supply presser line such that, in a valve body, a hole is drilled in a valve body to connect the solenoid signal line in a first area to a second differential area connected to the torque converter OUT line, and the torque converter OUT hole in the valve body casing is plugged.