Electric Radiator Fans

Trying to find the best bang for the buck in electric fans.

Also, look here for control/relay setups: https://sites.google.com/site/astrosafariinfo/engine/engine-cooling

1st Gen body style:

Still need to look...

2nd Gen Body style:

01-07 Toyota Highlander(rx300 years?), dual fans with separate connectors, radiator core is 1/2in taller and 1/2in wider, top and bottom mounting points, does it fit easily? Dorman 620-551

Use a time delay for the second fan to prevent both from turning on at the exact same time.

Power-On Time Delay Relay from www.bowdenshobbycircuits.info/page2.htm

Here's a power-on time delay relay circuit that takes advantage of the emitter/base breakdown voltage of an ordinary bi-polar transistor. The reverse connected emitter/base junction of a 2N3904 transistor is used as an 8 volt zener diode which creates a higher turn-on voltage for the Darlington connected transistor pair. Most any bi-polar transistor may be used, but the zener voltage will vary from about 6 to 9 volts depending on the particular transistor used. Time delay is roughly 7 seconds using a 47K resistor and 100uF capacitor and can be reduced by reducing the R or C values. Longer delays can be obtained with a larger capacitor, the timing resistor probably shouldn't be increased past 47K. The circuit should work with most any 12 volt DC relay that has a coil resistance of 75 ohms or more. The 10K resistor connected across the supply provides a discharge path for the capacitor when power is turned off and is not needed if the power supply already has a bleeder resistor.

http://www.gearhead-efi.com/Fuel-Injection/showthread.php?6149-1227747-electric-fan

1227747 electric fan control ------ I'm not sure if this information has been shared or not. I couldn't find it. The 1227747 ecm is not set up to control an electric fan. However, if you are not using an a lock up torque converter, you can use the ground signal from A7 to control the fan relay. See the attached picture for the TCC parameters I changed. Using the TCC - minimum CTC for TCC lock as the fan on temperature is the only parameter you have to experiment with. The only weird thing is the actual temperature that the fan turns on is about 20 degrees C higher than what is in the TCC - minimum CTC for TCC lock is set at. I'm not sure why.