a TwEECer will log when a car is in open or closed loop. I agree about the T-stat, if your;s is working correctly (closing when temps get lower than 180) then you shouldn't be getting to 163°.
Did you drill your stat or something? Because below 180 degrees it should close and your engine should heat up. I have a Fluidyne Radiator, 180 stat, and my fan temps set even lower with my tweecer and im always between 182 and 190 on my autometer gauge and my tweecer reading the ECT. I dont see how you could be that cold if the coolant isnt flowing(closed thermostat).
This thermostat came drilled, but I usually drill mine. Sorry, it would've helped to say that - I never thought about it. I realize that's the reason the temps are that cold, but I never thought they'd drop THAT far. I'm not really that concerned about the actual temp, as long as I'm not gonna damage the engine or mess up its performance.