stock thermostat is 195, I believe fans are set to turn on about 210, or if the A\C is on. I personally run a 195 Tstat Oct-Apr and a 180 May-Sep. I also cover 1/2 my radiator with cardboard when the temps dip below 30 degrees or so. The car heats up much faster, which equates to better MPG. My issue is that I leave work at 1am, and almost immediately drive 45mpg for 5 miles, then 65 for 10 miles, then 45 for 2 miles and then I am home. I may hit 1 or 2 very quick stop lights. Without the cardboard, my car does not reach full temp until I am over 1/2 way home. With it, I am at full temp when I reach the highway, 5 miles sooner.