Stop in for a cup of coffee
Lets look at the original expected coolant temps.
1966 Dodge Dart Coronet FSM
1970 Plymouth FSM
'
Notice with the earlier cars, 175 degrees is the minimum where the radiator is allowed to begin to aid in cooling. Further that full flow to the radiator is not expected until the temperature gets up to 200 degrees.
Lets look at the original expected coolant temps.
1966 Dodge Dart Coronet FSM
1970 Plymouth FSM
'
Notice with the earlier cars, 175 degrees is the minimum where the radiator is allowed to begin to aid in cooling. Further that full flow to the radiator is not expected until the temperature gets up to 200 degrees.