Ok, I have a new Ron Davis radiator that came with the dual Spal fans to replace my old single fan in my 1990 RS. The radiator looks great but this wiring thing just isnt clicking in my head yet. What is truely the best way to have these fans run, both on at the same time? I want everything to run properly (turning on with ac & with the temp switch, no manual stuff). So where do I tie into the existing wiring? Do I just tie one in at the ac and the other at the temp switch? If done that way will they both run when the ac is on then the temp climbs over the set point? And should my primary power come straight from the battery or isnt there a place in the existing wiring to tie in for that? I want this done right and looking clean, no radom wires running all over. I have been looking at wiring diagrams but I guess I am a little slow, cuz it just aint clicking for me yet? Any help will be appreciated. Thanks Mike

Hi, I´m currently looking at a maybe similar setup.

I also have a 1989 single fan TBI camaro in which the fan died.
I fitted a single 14" SPAL fan and a second 10" SPAL fan on the driver side.

I hooked up the 14" fan to the stock fan connector which makes it run when te engine exceeds 235 and/or when switching the airco on.

I found out however that the fan does not run when the engine is off, even if te temperature is still above 220 degrees.

Since I´m not quite happy with this (the stock temperature setup) I decided to get a new temperature sensor.

I could either go for, and this is the part which is undecided as of yet, the solution of repacing the stock temp sensor and get a set that wires up both fans over a non-stock relay



The other alternative is to use the stock sensor (basically use your original fan plus and minus to wire u one fa) and wire up the second fan with



This will allow you to set different temperatures for both the fans allowing for more tweakability athough I´m not sure if it would be a technical benefit compared to the first alternative.

Personally I do not like the stock setup rewired to fit two fans.

I hope all this applies to your situation and is of some help. Personally I´m undecided as of yet and currently do no have the funds to try both

So, do I tie one fan in at the ac unit and one at the temp sensor?

with the single fan setup in the RS using the stock fan wiring to connect a fan it will activate when the airco is used and/or when the set temperature is reached.

I found out by now that I would prefer this for one fan, and that in my setup I will wire the biggest of the two fitted fans to be controlled by an adjustable temperature sensor which will be radiator mounted.

This setup is not quite as versatile as willies total fan control as found in the stickies, but it will allow me first of all to leave the stock wiring as is, not need to fit any dash mounted switches and for smog tests I can manually raise the temperature setting on the adjustable temp sensor to 220 while leaving it at 180 for the remainder of the year.

I hope that makes sense?

If I want the 2 fans to run exactly as the single factory, can I tie the new Spal harnesses directly to the end of the factory one where it plugs to the original fan? (Did that make sense?)

Just be careful not to blow the fan fuse... How many amps are both of the new fans drawing together? I know a single stock fan draws about 20A when first switched on.

I don't know how many amps both fans will draw, I will have to find out. I am really slow to wrap my brain around this wiring stuff. (Sorry but that's why I have started other post) what if I run my primary power straight from the battery but hook to the existing wiring simply to turn the fans on with the ac and temp controls?

i used a flexalite controller for my dual fans. my fans came from a fourth gen. it works great and has two terminals on it that can be wired to turn them on 100% or completely off. nice piece.

The easyest quickest way to wire them I can think of is use the old fan relay wireing control circuit to turn the relay on then wire the power for the fans off the battery with a 30 to 35 amp fuse.

Thanks. Fans are running just like I wanted. They are alittle on the loud side though. Now I just have to figure out why my heat blew hot for a few min last night, then it wouldn't blow hot. I changed everything from the radiator to the heater core. Man this is a pain in my rear!

A lot of climate control problems can be traced to the vacuum retainer clip which is found inside the round vacuum plug-in chamber found behind your climate control body. It is spring loaded and it allows vacuum to route through little transfer slots to allow various blend door operations to work. If this spring tension breaks-you get no blend door operation-it's just stuck at whatever setting you had it at...defroster, vents, floor, etc. Check that out first. It's a common GM problem. HELP section at most parts stores used to carry that little item but as of late, they seem to be getting harder to find. Go stock up on low mileage GM units at the boneyard next time you go!