Most Factory torque converters are designed to stall around 1700 to 1800 rpms. But that is a function of many variables, and not a hard and fast rule. The most critical variables being torque input, final drive ratio, and vehicle weight. I.E. The same converter may stall at 1700 rpm when put behind a 6.9 IDI, but may stall at 2300 rpms when installed behind a built 460. Even changing the torque curve (cam change or turbo addition) of your motor will effect the stall point.