Aren't loiter time and range the same? It seems like if you can go 400km then that could either be 200km out and 200km back or it could be 100km out, 200km loiter, and 100km back.
Max Endurance airspeed and Max Range airspeed are two different things. For instance, in a 60S, max endurance airspeed is about 70 knots and max range is about 132.