dual fans wiring to switch
08-26-2014, 11:56 AM
#51
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Car: 89 Camaro RS running MS2X
Engine: .48/.60AR T3/T4 2.8L V6
Transmission: Rebuilt 700R4 2500 stall
Axle/Gears: Next to break...
Good thread. maybe you cn give me some help related to it
I'm considering doing a LS1 fan swap on my 86 trans am. I'd like to leave one fan wired the same as the single fan on my car. From what I understand the single LS fan with the shroud will do a better job than the stock fan on my car, but I also want a second fan that can be used for harsh temperature days, like days 100 degrees or above.
Here's my options.. Let me know what you think.
I know you aren't going to like this first one, but it's simple. Run a 12 gauge wire from the battery and a 30A fuse directly to the second fan, and have the ground controlled by a switch on my dash (i'm going to try to repurpose my subwoofer switch)
second option. Run a relay so the second fan come on when the car is above 220 degrees. i know this is the better way, but here's my question (sorry if they are dumb questions)
Does my 86 305 have the spot in the head to put a thermal switch? If it's not there or is already being used, what do I use to trigger the relay?
right now it looks like my single fan runs all the time, even when the car is cold. Does that mean the thermal switch or the relay has been bypassed?
I don't mind doing it the right way, I just need an education on how to get it done
I'm considering doing a LS1 fan swap on my 86 trans am. I'd like to leave one fan wired the same as the single fan on my car. From what I understand the single LS fan with the shroud will do a better job than the stock fan on my car, but I also want a second fan that can be used for harsh temperature days, like days 100 degrees or above.
Here's my options.. Let me know what you think.
I know you aren't going to like this first one, but it's simple. Run a 12 gauge wire from the battery and a 30A fuse directly to the second fan, and have the ground controlled by a switch on my dash (i'm going to try to repurpose my subwoofer switch)
second option. Run a relay so the second fan come on when the car is above 220 degrees. i know this is the better way, but here's my question (sorry if they are dumb questions)
Does my 86 305 have the spot in the head to put a thermal switch? If it's not there or is already being used, what do I use to trigger the relay?
right now it looks like my single fan runs all the time, even when the car is cold. Does that mean the thermal switch or the relay has been bypassed?
I don't mind doing it the right way, I just need an education on how to get it done
If using dual fans, you can wire one like stock, with the fan switch in the head and a relay. For the second fan, wire it the same way as the first, but instead of running your ground wire for the relay to the fan switch, run it to a toggle switch then to a ground from the toggle switch.
GM used relays for a reason. The high load power and ground that powers the fans will melt the wires, if not the wires then the switch. The current will take out the weakest link. Just use a relay and you can wire it however you want.
Chances are your current ground trigger for the relay is either short to ground, or the PO wired it directly for ground. The original fan switch will only be used for the fans, so it is most likely unused right now if the relay is wired straight to ground instead of the fan switch in the head.
Last edited by willexoIX; 08-26-2014 at 11:59 AM.
08-26-2014, 01:38 PM
#52
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Car: 89 forrmula
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Re: dual fans wiring to switch
Keep in mind too that the LS fans are quire a bit more stout than the original fans so I would suggest using 40 or 50 amp rated relays. GM wired them in series for low and high speed which among other benefits, serve to reduce voltage spiking-I would wire your LS fans exactly how GM did using 3 relays and use 2 temp switches to act as a stand alone from your stock ECM and you should be good.
08-28-2014, 09:49 PM
#53
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Car: 89 forrmula
Engine: 350 TBI
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Re: dual fans wiring to switch
Or, if you do find some LT1 or even TPI dual fans, I wire them so that they both run @ up to three speeds using a resistor board. I also upgrade my wiring so that there is never a problem should I decide to upgrade further....here's a couple pics-all new stuff....I even like to add the weatherproof 630 series inline fuse holder.
08-28-2014, 09:52 PM
#54
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Car: 89 rs, 86 Trans Am
Engine: RS-V6... Trans Am-LG4
Transmission: RS-T5... Trans Am 700r4
Re: dual fans wiring to switch
you build those? ready to install?
I have a set of LS fans available to me
I have a set of LS fans available to me
08-28-2014, 10:49 PM
#55
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Car: 89 forrmula
Engine: 350 TBI
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Re: dual fans wiring to switch
Ah....well heck yeah if you already have a set of LS1 fans then go with those! They are just as good-GM wired them in series for 2-speed operation and that's the way I would go with them if you are using ecm ground trigger outputs-otherwise, a 3-speed stand alone option would be nice too. Depends on which route you want to take-either way is dependable.
05-17-2020, 12:25 AM
#56
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Car: 98' Oldsmobile Cutlass
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Re: dual fans wiring to switch
I know nthis post is old but would you be able to give me a quick run through on all this.? I already printed your diagram and comments out but I just some advice on my setup.I would greatly appreciate it.
05-17-2020, 09:30 AM
#57
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Re: dual fans wiring to switch
This thread is rife with TERRIBLE information. I would disrregard everything here and start your own thread starting with your car make and year with options, to best help you for what YOU need
05-17-2020, 09:55 AM
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