I finished swapping a jdm b18c into my gsr and it runs fine with no major problems or codes but it seems that the motor never gets to optimum running temperature while i'm driving. The temp needle fluctuates all the way from 3mm past C to less than half way all while dirving. It doesn't stabalize anywhere and does not overheat either. I removed the AC and the AC condensor along with it which sits in front of the radiator. I'm guessing this is causing more cool air to hit the radiator cooling the coolant down too much? Could a bad thermostat cause this to happen? I always though a bad thermostat causes the car to overheat. Another thing is the car will reach optimum temp while sitting idle and fans come on as normal while just sitting idle. Any ideas?