on a day where it's only in the 50's or low 60's it will hardly break 160. I have two temperature sensors in it. One in the block and the other right above the thermostat. I don't see how the block sensor is all that accurate since it's sitting right above the exhaust manifolds. It's kind of cool cause I can see exactly when the thermostat opens. Nifty little diagnostic thing. If my block temp raises and my thermostat gauge isn't coming up then the thing's stuck shut. If it's coming up slowly then it's stuck open.