So I am installing a second fan switch so that I can run a dual speed fan (FORMULA1LE's Fan Relay system), but the only real spot I have is in the intake where you can see the attached pictures. Am I stupid to put that there in that it'll wear through the hose? I might be able to put some old hose around it to protect it?

Any thoughts, gripes, bitches, or concerns? All input is welcome. Thanks!

 

I wouldn't do that...

Instead, I'd drill and tap that pre-69 alternator bracket boss right under there, and put it there.

 

Yeah, I don't know how to drill and tap something.

 

If you aren't able to drill and tap , one possible other suggestion may be to see if there are any other thermostat housings available that might bring the hose off at a better angle so as to not hit the switch ? For that matter have you tried loosening the clamp and repositioning the hose to try and gain a bit of clearance ? I do believe it will wear through the hose if left the way it is so something will need to be done . Are there no other unused pre threaded holes in the heads or manifold you could take out a block off plug from and access the coolant flow there ?

 

I didn't see another plug. I have one in the passenger head, this is a for a secondary "early" turn on of one of the fans (I'm retrofitting a dual fan set up into a single electric fan car).

I will look into water neck housings, the only issue there will be being able to use the factory upper radiator hose if I change the angle too much.

 

There are a couple of options, one of which is a thermostat housing with dual openings for a second sensor. I just don't necessarily want to spend another $40 or so right now to buy one. May have to wait a while. I think I have a part of water hose that I will be able to use as a shield so it won't rub directly in the mean time.

 

Use the block plug on the pass side of the block, where TPI units put the 2ndary fan switch...no muss, no fuss

 

Where is this plug in relation to the where the normal fan switch goes on the passenger side?

 

Where the KS should be? I'm not aware of any 'factory' fans that had a second mechanical controller.

The stock water neck for your motor should have a boss for the CTS (which I see) and the EFE. You may be able to use the EFE boss if it's large enough.

Drilling and tapping the manifold would be fairly easy, although I don't think you should try it while it's installed.

 

Thinking about it, is it in the head?...down and below #6 and 8 plugs, i/e will be just opposite of the one under #1 and 3 plugs on the driverside.

I think it is in the head, the one in the block is for the Knock Sensor.

 

I am using the one factory slot in the head which is what currently runs the factory single fan.

I changed water necks when I built the motor and took out one of the connectors. I left the one electrical connector and one that goes to the diverter valve thing (Holds the big vacuum line coming from the carb and goes to the PCV valve, not in picture because I pulled the lines to have room to work), but it's installed in the top of the intake on the passenger side. The other connector I removed.

What exactly is the EFE?
I've looked at several other water necks but don't see any that would deviate from this design enough to give me any more room.

 

Factory dual fan setups ...the ECM controls the primary fan relay, the 2ndry fan relay is controlled by the Fan Switch in the pass side head.

 

Correct. I typo'd. Should have read 'second' mechanical controller, as in two temp switches. Although the 84 doesn't have a KS (unless it's an L69?) I still wouldn't recommend installing a second fan switch in the drain plug. Too often clogged up with gunk sediment.

 

I'm already using the one in the head for my factory fan sensor. My car is a single electric so it uses this one normally. I need a second sensor to run my new dual fan set up.

 

It was an L69 car (now 355).

 

Sweet. I should have remembered.

The EFE was controlled by the second thermal vacuum switch on the stock water neck. If you have room, a stock style water neck is only a few $ (but will likely be cast vs aluminum).

 

I will need to look at Autozone. Rock auto has 2, one for $6 and another for $30. Both with the two ports like in your picture.

 

Right, but there should be plug in the other head below 6 and 8 you can use...right now you're using the one below 1 and 3, right?

 

I'm using the plugs on both sides of the motor. ON driver side it's for the Temp gauge. The one on the passenger side is currently used for my factory fan switch which will still run one of my two fans.

I'm installing a dual fan set up so I need a second, cooler fan switch to turn on the first of my two new fans. The factory switch will still run the other.

 

I see.

 

Pretty sure that's the one the single-fan cars use as their primary fan switch port, just forward of the dipstick. I'll take a look though it's pretty crowded down on that side of the motor.

 

Check the water neck at the store before you buy. The EFE bung may be too small for your temp switch.

 

When I swapped mine, I did it from under the car.

 

One other thing, you could have the FanSwitch control both fans...on my car, when I swapped to a lower one, it makes both fans come on at the same time.

 

That is my idea actually.

I finally received my new Fan relay set in the mail today. It was made by Formula1LE here on the site.

It's a "voltage" set relay that will turn both fans on when the lower temp is met, but limit the voltage to 7 volts or so. Then when the second temp kicks on, they'll be on "high". They'll also be on "high" when the AC is turned on.

 

Why 4 relays?...TPI cars have two, just curious?

All that is needed to control two relays is 12V and the FS switching to ground.

Is this set up to have one come on earlier, then the next?...just curious is all...

My feeling in stop and go when the fans come on...pull the air with both of them, why wait?

 

I just used two temp controlled adjustable fan controllers .

Any way, just a heads up, and you may already know this, but run your wire the wrought you want to use, give it a little slack then cut it and push the wire through the wire loom before you do its finale install.

I learned the hard way.

 

OR you could install two separate, independent systems such that a failure in one circuit will not affect the operation of the other fan...

There's also little need to run both fans in sync. In most cases one fan is enough. With both fans operating you're mostly just stressing the electrical and charging system and wasting more gas.

The staged controller is nice provided each controller is independent and the lower voltage does not over tax the motors.

 

The build is of very high quality. Both fans comeo n when the first relay trips at 195* (the new temp switch), and then ramp up their speed at 212* to full. They will also come on full with the AC. Power comes in through one of the relays, the other three run the fan speeds from how I understand it.

I do know, that with the dual fans installed but only one running (only one factory plug) using the factory system, the car in stop and go runs the temp up around 240 before holding steady, but there isn't enough airflow to cool it down. If I turn the AC on it boils over fairly quickly.

I will leave the factory system in place as a backup, but this will run the dual fan set up as an independent controller.

 

Good info, thanks!

 

Ozz1967,
I like what you have planned.

I've been using this circuit for many years so thought I would share it .
I hope you don't mind.

There are a few different ways to get two fans to come on at two different times.
Here's mine.
Two relays, two fan controllers ,= Two independent circuits. = Around $60.00
I wired in two of these circuits. One fan comes on at 180* and the other at 190* with a 180* thermostat.

Side note =
With this circuit fans can be set at any temp you want but I believe with a 180* thermostat the first fan should come on at 190* and the second at 200*as back up.

I have my fans coming on earlier than that but that's because they are working with an axillary trans cooler that I want to keep at lower temps.