I don't want to start a mondo debate but I wonder what others program their fans to come on and off at?

I had mine programmed to come on at 190F and off at 175F


I ordered the PAC-2700, Electronic Fan Controller 70 Amp,

The PAC-2700 was designed for the ultimate in flexibility, and to be a simple add-on in any application using an electric fan. Included is a 70amp relay, enough for even the most power hungry of cooling fans. Fully programmable, the PAC-2700 will work with many existing electronic water temp gauges which indicate a numerical temperature reading (as opposed to " Cold, Normal, Hot", etc), operating from the single-wire temperature sending unit already installed. A dedicated sending unit can also be installed.

The PAC-2700 features fully programmable “fan on” and “fan off” temperatures to suit any application or personal preferences. The PAC-2700 has the capability to leave the electric fan operating after the engine has been shut down for a user adjustable time. The PAC-2700 offers a full digital LED readout for displaying temperature readings and maintaining simple installation.

Box measures 4" wide, 2.5" high, 1" thick. Mounting is recommended inside the cab of the vehicle or an alternate dry environment.

Fan Temperature Selection Range: 150F- 250F

**The use of a second relay RLY-1 (0-30 amp) or RLY-3 (0-70 amp)(not included) will be required for dual fan or two speed fan operation.

The PAC-2700 features a 24-month warranty against manufacturer defects!

I believe mine is programmed at 205 on and 190 off. Much lower than that and your fan will be constantly running. I'll have to double check it, but that won't be until I do some more datalogging.

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That's a good point, I have the Dewitts fan and I think I will set it higher to 200 and off at 185

I have mine at 215*on,199* off with a 195* thermostat.
Mine is a stock 89.


Joel

I do not have a controller, I just use a 190-180 temp switch for my single fan 1984. Comes on about 192 and off at 187. Car runs at 186 on the highway and 190 around town.

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A good idea for your 1984 but that won't work on later models. The 1984 uses a temperature switch on the passenger side head to control the fan on/off, later models use a temp sensor and are triggered through the ECM for the primary fan, so you need to change the settings in the tune.

Matthew

Mine comes on at 195* and off at 180*
I run around town in the middle of the summer in 100* south Texas at 170-177 depending on driving speed. When sitting it gets up to 195* and shoots down to 185* until I start moving again.

Dewitts+Spal FTMFW

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Typically on late cars ,the aftermarket switch is wired in parallel with the ECM control ( to ground ) so fan(s) operate off the new switch but will run from the ECM at default temp setting should the switch fail

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Yea, easy to do.

But this mod does throw a Code for the Quad Driver #4, it doesn't hurt anything though. You just clear the code if you feel like it.