Well, the fan should come on at the same temp all the time. Does the temp gauge go past the "R" in NORMAL? Did you remove the vent bolt when filling the system, filling it until fluid reaches the vent plug hole and then squeeze the upper rad hose to purge any air out while the car is running with water pump circulating? Also just a FYI that you probably already know but the only other time the fan will come on at any temp is when you turn on the AC MAX.
If it seems excessive, be sure you have plenty of water in your mixture (55%H2O&45%glycol). Keep an eye on that trans fluid. Keep it fresh. Also, there is an additive you can pick up and pour into the radiator to help cool it down quicker called "Water Weter" or "Purple Ice" and B&G makes one too thats excellent. Hope something there is helpful. Good luck.
