[Stocker]

All good advice above, I will agree with a 195* thermostat, no t-stat lets the coolant go through the radiator so fast it doesn't have time to cool off, if that makes sense.

One thing you didn't mention is what type of fan you have. If you have a fixed-blade or a flex fan instead of a good clutch fan, I would strongly suspect that is the problem. My factory A/C 350 has a 7-blade clutch fan and zero cooling issues.