Thoes temps sound about right I have been checking mine to make sure my fan is set right and I have been running about 3 to 6 degrees above my thermostat temp of 170. And the spike is 9 to 11 degrees above when the fan kicks on. That is with an ambiant temp of about 70 to 80 degrees.

 

the stock water temp gauge will show the "normal" operating temp on it until the actual water temp reaches about 240deg... then it will start to climb up.