Quote:
Originally Posted by Paul Workman
I never took 'thermal dynamics', so I don't know the proper physics terms for it. But, you're right: The greater the heat differential between the radiator (coolant) and the ambient air, the greater the rate at which (therms or calories or whatever) will transfer (to the air, in this case)*. *Plotting the temp over time, the graph would describe the change over time according to the natural log of decay. This would explain why it usually requires a lager capacity radiator and sometimes increased (fan) air volume coupled with a lower temp thermostat to bring the coolant temperature down to the lower 'stat opening point. IOW, the closer the coolant is to the ambient air temperature, the slower the coolant temperature falls (unless and until the motor adds more heated coolant to the radiator), all else being equal. |
I took Thermal and other stuff but much easier to explain with just plain logic.
When both the cooler and hotter Thermostats are fully open (assuming both allow the same flow) there is NO advantage using the cooler Thermostat. When it is HOT outside and you are operating above the full open Coolant Temperature of the Hotter Thermostat.
There is a DIFFERENCE however when operating on COOLER Days when the Coolant Temperature does NOT rise to the FUll OPEN Conditiaon of the Hotter Thermostat. Then you are operating with a PART OPEN 180 deg Thermostat and maybe a FULL OPEN 160 deg Thermostat. Or when really cool outside. A PARTLY Open 160 deg Thermostat and a CLOSED 180 deg Thermostat. In OTHER WORDS your Coolant Temperature is Held Below 180 Deg which is NOT GOOD for the LT5.
The LT5 is designed for 180 deg I think as that is the Thermostat it comes with albeit my 95 had a 190 deg Thermostat which I changed out for a 180 deg (I think the 180 deg original Thermostat just drifted to a higher opening temperature with age as Marc suggested).