I need to know if its possible to make a manual fan switch for a 87 IROC. Thanks

 

yes it is. all you have to do is splice the wire from the switch to the driver side fan. this will allow you to manually turn it on. this doesn't work so well if you have a lower temp fan switc, but it works great with the factory temp fan turn on switch that turns on at 230*. however, a 186 temp switch will take care of the heating problem. my advice is to run te switch from the ash tray down the side of the center column and then under the dash in throug the hole in the firewall where the ecm wire go through

 

Read my article:

http://www.thirdgen.org/newdesign/tech/cool.shtml

You might also want to check out my switches. Click on "SC Z!!!" in my sig, then scroll down the page and click on "Switches".

 

I had my main fan running all the time on my bird, and had the a/c fan setup with a relay under the hood, and a switch in the car, so if I was in heavy traffic, I could switch that baby on, and that helped get some heat out, but my car ran between 140 and 160* anyway, so heat was never a problem. I just bought an 87 iroc-z too but for my daily driver, my 89 formula 350, soon to be running high 10's low 11's is my real pride and joy.

 

i have both fans on a switch.
the switch grounds the relay

 

yeah if you use factory ones, I used my own relays, and spade terminals instead of the factory ones.

 

Thats exactly what I want to do. Could you explain what you did a little better? Mainly what wires did you tap into and where? I am guessing you only had to tap into two wires, then supply the grounds on the switch for them, correct? Also, do you have any LEDs working with it to tell you when they kick on? Thanks a lot

I have a 4th gen, so I don't know to much about the 3rd gens, but so far this soudns like the setup I have in my '94.

Oh, are any resistors necessary? thanks again

 

I tapped into the ground wires at the relays and ran the wires to two switches I mounted under the my dash area.


I then ran two wires from the switches to a screw under the dash to provide a ground, so when I use the switch it completes the ground for the relay and the fan comes on.
I don't have any indicator lights at the moment and by using the grounds I don't think I can get the lights in the switches to work.

 

Okay cool, so do you just have two seperate switches, because I don't know what the 3rd one is for. How would you wire up an LED if you had to?

 

The 2 red ones are the fans, the blue one is nothing at the moment.

I could run an LED from the power wires at the fan up to the dash for an indicator, which I may do in the future. That would probabaly be the easiest way to do it.

 

Well, this is for another guys car, so could you help me a little more? Where exactly is the relay that you tapped into? I am not even going to be able to see the car, just trying to help him out.

There are two separate relays for the high and low speed right? Thanks

 

87 Iroc will have single speed fans.

On my 88 Formula, one relay was on the pass side of the radiator and the other was on the pass side fender.

If your friend traces the wires from the fans, they'll end up at the relays.