I have a '70 Trans Am with the original Ram Air III engine. My temperature gauge is reading to low (just over 100 degrees on the gauge). The thermostat is working since the engine is running at a normal temperature (after driving the car the manifold and head temperature is between 195 and 205 degrees. I have the original temperature sending unit in the car so I'm thinking it may be had. I have tried two different dash gauges and get the same reading.