one03sierra

iTrader: (1)

i bought mine directly from them.

eallanboggs

iTrader: (1)

Your fans don't need to line up with you motor. They need to line up with your radiator. Look at the Super Comp cars. They have a remote radiator with a little electric fan to push air across them. They are mounted horizontally BEHIND the engine so they get NO air flow at all as the car is moving. If you don't use a DIGITAL controller of some sort you can just use relays and an adjustable thermostat from flex-a-lite as your control. You need one relay to turn the fans on when you reach operating temp and another to turn the fans on immediately if you switch on your A/C before you engine warms up. As long as you know basic electricity (Ohms Law) you can do this stuff in your driveway. I would solder everything. Crimps are not always sound mechanically or electrically. You need a schematic to find the right trigger wires to pick your relays. The pulley is a good idea too. You get a noticeable gain from it.

LS1S10

Ya, i know it will cool without the fan being inline with the motor....but it does help a little with effeciency if the air off the back of the fan blows across the exterior of the motor. No biggy though, i figured it would work fine. Im probably going to wait until i get back from Savannah to tackle this, along with the pulley. I wish my local track would let me make a run in my truck.....friggin tech wont let me run on my tires So i guess i gotta go by SOTP for any gains i get off each mod. Oh well.

SnakeOiler

iTrader: (6)

Does anyone have a schematic for the 3-relay hookup of the fans that runs off of the PCM?

eallanboggs

iTrader: (1)

You need a schematic that is specific to the vehicle your working on by year and model. The PCM wire probably provides a ground so you would connect that wire to the coil of the control relay at either teminal 85 or 86. The N.C. contacts of that relay would go to the fan. You connect teminals 30 and 87a of the relay to 12VDC and ground to turn the fan on when the PCM provides the trigger. It doesn't matter which of those terminals is HOT or GND, but you do need to know if the PCM provides a GND which is most likely the case. The coil of the other relay goes to the A/C circuit. You can tap into the A/C relay coil circuit or the A/C clutch circuit to pick the relay that your using if you turn on your A/C BEFORE your engine warms up. The N.C. cntacts of this relay also go to the fans. If you have a schematic and know basic eletricity you won't have a problem making these connections. Use solder connections. Only make crimps on vehicles you will never see again.

SnakeOiler

iTrader: (6)

so, something like this would work OK?

one03sierra

iTrader: (1)

yes but the truck pcm only provides one ground. the fbodies have two. hook one up to the a/c. but it will be positive.

eallanboggs

iTrader: (1)

Sounds like a plan and you only need one extra realy to get the circuit to operate that way. Relays are cheap. Just solder everything and use plenty of wire ties to keep things neat and out of harms way. Are you using a low temp thermostat. That will bring the water temp down too.

SnakeOiler

iTrader: (6)

I have a schematic of both: using the A/C clutch compressor relay ground control (previously attached) and the A/C signal request, +12V (attached here)

I just didn't know which way would be better.

3-relay

eallanboggs

iTrader: (1)

If you go back to ohms law you know that when you tap into a circuit you are creating a NEW parallel branch circuit. Ohms law says each branch sees the source voltage, but the current different depending on load. That means it doesn't make a whole lot of difference which circuit you use to trigger your fans. Just find one that is easy to get to and use shrink tubing and solder everything.