Electric fan temp settings

Cougar Community Classic Cougar Maintenance Restoration and Repair
1

I’m running a 408 with aluminum heads, putting out about 500hp at the flywheel. My engine builder recommended a 180-195 degree thermostat.

According to the stant web site their thermostats are fully open 15-20 degrees above rated temp. So I put in a 180 degree thermostat with the understanding that it would begin opening at 180 and be fully open between 195-200 degrees.

Now I’ve got the Fitech fuel injection controlling the electric fan on/off temps but I’m not quite sure what to set them at.

I don’t want the engine to get too hot before they kick in but also have heard that you shouldn’t have them fighting the thermostat.

I’m thinking about on at 205 and off at 195? Anyone have experience with this?

2

From my own research it seems the rule of thumb is to have the fan turn on 10 degrees over your thermostat setting.

3

On my 408w in the race car. I have a 165° thermostat and the fans turn on/off at 180°. it’s always 50° air temp and warmer when I’m running the Cougar. Generally in the 70’s & 80’s. I also have an oil cooler installed that helps, but also impedes some of the air flow thru the radiator.