OL'55,
I lived in Palmdale for several years with my 1950 3100 truck with a 1957 235. You have extremely HOT summers and cold winters. I found the 180 degree worked best. Those 115 degree days the temperature would run 190 when I was ON the gas (3 speed original 4:11 gears). Winter I had Nice warm heat out of my 6 volt Arvin heater. Good luck.
Todd


1950 Chevy 3100