Just curious as to what temps you guys out there have your controllers set to turn on your Electric Fans? And what would be considered the best temp to have the fan come on?
Gonna depend on what your fan thermostat rating is and what temp your car runs at. Some fan thermostats have an on/off temp range rather than a specific single number for on/off. For example, 205 on, 195 off.
For example, my car runs at 185-188* (verified with auto meter mechanical gauge) on the highway, or with the fan on. My fan thermostat is set to come on at 195.
So that means most of the time, my fan is off. If I come to a stop and idle for 5 mins at a light, then the fan might click on and the temp will fall to 185ish or so and click off.
I am running a Flex-A-Lite controller with my Contour dual fans and I am using a 180 degree thermostat. I have been setting my fan to come on anywhere from about 182 to 195 depending on the season using my Auto Meter mechanical temp gauge. So it sounds like a setting of 185 to 190 should be a happy medium for me.
If you set the fan to come on too low, it will constantly be cycling which will do a couple of things- wear out the fan faster, and the engine will not run as efficient. Best is to set the temp like MFE suggested. If you don't have a mechanical gauge to set it, you can ballpark it by setting the fan to come on when the thermostat opens up and you feel the upper radiator circulating hot coolant. The stock gauge is not the most accurate, but the lowest mark is 140 and the highest is 270. and each increment is around25 degrees. There's 6 increments between the marks so that can give you an estimate of where the car is running.