I just wanted to add something here ..............when your sensor for the temp gauge is located at the front of the manifold near the top hose outlet.............what you see on the gauge is the temp of the coolant at it's hottest point and if the fan,pump and rad are doing their jobs, the coolant temp in the block can be 20-30 degrees cooler than what the gauge is telling you. Also the coolant temps that are passing the sensor are also coolant that's leaving the motor. The gauge is not registering what temps are in the motor, only telling you how hot the coolant is leaving.