Engine Ice is propylene-glycol and has only 80% of thermal-conductivity of regular ethylene-glycol. And only 60% of thermal-conductivity of water.
As test, change your coolant to distilled water + WaterWetter. You'll find temps will be lower because more heat-BTU/sec will be shed by radiator.
As test, change your coolant to distilled water + WaterWetter. You'll find temps will be lower because more heat-BTU/sec will be shed by radiator.