S (stall point): In this particular issue the turbine speed is zero plus the impeller is rotating; the efficiency while in the stall point is minimum amount, close to fifty%, which means that half of the facility coming from your motor is missing through friction and dissipated as heat; at https://torqueconverterclutch55296.bloginder.com/34919805/the-definitive-guide-to-torque-converter-clutch