My engine wasn't cooling as I had the electric fan mounted in front of the radiator and no viscous fan I probably had it moving air the wrong way too. Well, I replaced the thermostat and fans switches with 75C ones and I was in the process of reinstalling the fan when I was testing the spin direction and the fan somehow caught my shirt and broke two blades off! Well I ordered a new fan rated at 2700 cfm which will arrive tomorrow. In the meantime I found a replacement fan blade for my original "new" electric fan, which is now on the way.
1. I was wondering if I can mount two different fans but of similar power next to each other behind the radiator without a shroud? One fan is 2700 cfm, the fan that I bought new blades for is rated at 2400-2700 cfm depending on the configuration IIRC.
2. If not, then I want to mount one behind the rad. and one in front. How would I configure the front fan to move the air correctly? See Pic below.
3. How can I wire the two fans so I don't fry anything. Will I need another relay? I just installed a rebuilt alternator and my battery is less than 3 months old. The systems charges properly, but I dont want to overload it. Thanks, Borys.

 

I believe you want both fans setup such that air flow passes through the first fan, through the radiators, further pulled by the viscous fan and blown against the engine.

outside air -> elec fan -> radiator -> radiator -> viscous fan -> engine

 

I have removed the a/c radiator and viscous fan, so I am going with two electric fans. I know others have used two electric fans on either side of the radiator. Anyone got pics and advice on how to wire that?

 

1) You could, but ideally you want to use a shroud so that air gets pulled through the entire radiator surface instead of just one or two circular areas.

2) Ideally for this setup you would have two different fans, one puller and one pusher, both mounted with their flat faces against the radiator(or at the shroud opening edge). Fan blades these days are usually profiled to optimize flow/noise in one particular direction. Usually the housing will have arrows that point in the direction of rotation and direction of air movement. Usually you can wire one fan backwards if you have two identical units. Usually it will run noisier, less efficient, or both if you do this. Don't get hung up on clockwise/counterclockwise; just make sure they both move air to the rear.

3) I'd say put another relay in. Those fans are probably drawing ~17amps each; two is a bit much for the factory wiring I think. You might want to run them off of staggered temp sensors so that one comes on at a slightly higher temp, especially if you find yourself idling in traffic much. That way, you only draw full current when you really need it.

Another possibility is to mount the fans front & rear, but not directly facing each other. Stagger them side to side. Having them directly lined up with each other will not double the flow, though it will increase it. You'd be better off moving air over a larger surface area.

 

Does anyone have a diagram showing me how to wire in a relay with two fans if I want to use the OEM switch on the lower right front of the radiator?

 

Mark K. originally replied to one of my posts and said that he ran dual fans through the factory relay. I run dual fans through the original wiring, relay, and fuse and have had no problems for over four months now. The fans regulalrly cycle on and off while driving around town. I believe the most important thing is to make sure that the fan's combined amperages do not exceed that of the factory relay which I believe is 25 amps. My combined amperages with the fans running is 18 amps. Hope this helps. Joe.

 

I don't have a diagram, no... but basically, the main power feed should probably come off the jump post, go through an adequate fuse, then to one of the switched terminals on the relay. The output terminal then goes to the fans. The coil connections on the relay would then be connected to your original fan wires.

Joe, IIRC Mark K has his fans hardwired.... he just flips a switch and they're on for the whole race.... or trip to/from the track.

 

Just a quick update. My new zirgo 2700 cfm fan arrived yesterday and I installed it today by itself since my replacement blades havent arrived for the other fan. Fired her up and drove around for about 20 minutes, then parked and let it idle. Temperature rose to 1/3 of the way between the first and second white line, and I popped the hood to check if the fan was on...and it was! pulling air like a champ. The cultprit deifinitely was the fan switch. Hopefully my other blades will come in tomorrow and I can install the other fan. Thanks for everyone's help.