Aux fan
Thread Starter
Racer
Joined: Jan 2004
Posts: 380
Likes: 0
From: New Hampshire There's nothing like a 'Vette
Aux fan
I have an '85 4+3 Z51 coupe. I've only had it since December and the PO didn't know much history on it. I believe it may have an aftermarket chip in it since the main fan comes on at an indicated 184 degrees. I know I could change the temp switch in the right head with a lower temp one from Eckler's and others, to have the aux fan come on earlier. I'd like both fans to come on at the same time. Does anyone see a problem with jumping between the main fan relay ground wire from the ECM to the ground on the aux fan relay? I wouldn't think the extra current needed to close the other relay would cause the computer any grief....or would it? 
Team Owner
Joined: Sep 2001
Posts: 62,160
Likes: 1,733
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
Why do you want them both to come on at the same time, you shouldnt still be having cooling problems if the main fan is reset to come on sooner.
Le Mans Master
Joined: Dec 2000
Posts: 7,839
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From: San Diego, Ca
Plenty of Vettes came without the aux fan and if your cooling system is up to par, you don't need it. Also, by the time the engine reaches the temp for aux fan operation, that temp can be high enough to minimize the available amps from the alternator. The extra load then slows down both fans and temps climb even higher.
