Dual Radiator Fans

ctuinstra

Well-Known Member
On my SC/SS, there are two fans on the radiator. I still have both wires in the engine harness, but need to extend them. But not sure which one, they are not colored the same nor do they originate from the same source. One uses light blue and a white wire while the other was gray and black I believe.

I assume there is a difference between the two such as one runs for the water temp and A/C and the other possibly for the supercharger cooler. Why would they run them completely separate?
 
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ctuinstra

Well-Known Member
I did some research and found out instead of using a low and high speed single fan, this car has two fans and fan one is for normal operation and then fan two kicks in for high speed operation. Not sure still which one should be the one that gets extending to the front. I assume fan one.
 

JSATX

Well-Known Member
IIRC first one comes on at about 212° and then the next one comes on at 217°.

My temps have never hit that high so far. Even on the track in the Texas summer I run 180-190°.
 

ctuinstra

Well-Known Member
If I keep going here I will answer all my questions by just typing them out. According to the wiring diagram I have, during low speed operation the two fans are effectively in series with each other effectively running them at half speed and then during high speed operation, they switch to parallel and both operate at full battery voltage. With this in mind, I cannot extend just one pair of wires. I believe I will have to extend the light blue wire and then permanently ground the negative side to the frame up front.

I'll bet this is in the build videos somewhere. I looked earlier and didn't find it.
 

Johvans

Well-Known Member
I believe I will have to extend the light blue wire and then permanently ground the negative side to the frame up front.

I'll bet this is in the build videos somewhere. I looked earlier and didn't find it.
Correct! It is split into two videos. They talk about grounding in the first part of build video 19 and then extending the light blue wire in build video 20. You are on the right track.
John
 
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