MY87LT

iTrader: (2)

Even though I have been pretty satisfied with my single fan set up, I've decided to go factory dual fans. After reading about this conversion and the hassles or ease of electrical connections from other posts, I want to do something special but need some opinions on the matter.

I was thinking before I install the dual fan setup, was to paint the actual fans with high temp paint either yellow like on some European cars or maybe a dark red. What do you think?

8t2 z-chev

you won't need high-temp paint,but will need paint that sticks well to plastic-i tried "fusion"paint on a GM fan shroud once and it worked great-withstands pressure washing with no peeling.The little electric fan on my '71 Saab is bright yellow plastic.How are you planning to connect the dual fan motors?-IIRC,some later model GM cars use a series/parallel motor connection relay setup on dual fans to get low/high speeds.

MY87LT

iTrader: (2)

Yea, I always loved those yellow European fans like on your SAAB and on FIAT, and other cars. As far as connections go, it's going to be either both on at the same time or get creative and have one just controled exclusively by the in head temp sensor like my current factory single and the other only to come on when the A/C is turned on. Still reading up on the electronics of it all.

Ron U.S.M.C.

I have two fans .One fan comes on earlier than the second that works as backup for the first fan. They are temperature controlled.


That's what I suggest.
Run them like that but incorporate the A/C.


I don't have A/C so I did not have to incorporate that system into my circuit.


Do not run two fans on the same circuit. The stock wiring and relays are not rated for that. It is not going to sustain them. Both can go out at the same time resulting in a serious, pegged, red line.

Ozz1967

iTrader: (4)

I did the single to dual fan conversion and have mine set up similar to Ron's above except both of my fans come on instead of one, then the other. Using a voltage drop relay system, both fans come on at 50% (6 volts) power at 195*, and then at 212*, the second relay drops to 90% power, about 10.5 volts, and the fans kick to a higher speed.

When I turn the AC on, both fans come on at full power.

So, same basic set up, just wired a little different.

Also what Ron says about the wiring is correct. Use a separate circuit for each fan.

MY87LT

iTrader: (2)

Thanks Ron and ozz. These are two very good ideas. Btw my current single fan comes in at 200 and off at 180.

MY87LT

iTrader: (2)

Got my dual fans today off an 1988 Camaro. Good thing I didn't get the wiring for it. Turns out that 1987's had different connections for the fan relay and my single fan wiring seems to be part of the harness of sorts. I could be wrong. Need to really look more into it.

abray1

Look into a Taurus fan. Last fan you will ever get.

Ozz1967

iTrader: (4)

Formual1LE here on the boards makes a killer wiring kit for dual fans. I've got one and love it. You can also go painless or any number of other aftermarket brands from Summit or Jegs.

Ron U.S.M.C.

This is the best way I have seen to wire in dual fans especially the temperature settings.


I run my primary fan at a much lower temperature because its also cooling a large transmission cooler.

Ozz1967

iTrader: (4)

That makes total sense if you're also running a transmission cooler. Does this aux cooler also have a fan or is it just a normal plate or tube-fin style?

MY87LT

iTrader: (2)

Already have the GM fans.

RS Chris

When I did my swap I used the stock harness for the passenger side fan. Works just like stock. For the driver side I wired in a stand alone circuit on a switch. It runs through a 30 amp fuse, then a 30 amp relay to power the fan. It can be turned on whenever I need it to be. It does require you to keep an eye on the temp gauge if it starts to get hot. For me I like it because I watch the gauges regularly, and I like to play with switches. But for others it may seem like to much hassle. Something to think about.

Ozz1967

iTrader: (4)

Get a set of TPI fans, LT1 Fans, or LS Fans. Both of the latter will need to be modified slightly for the bracketry to fit.

Painless and some other make an aftermarket set up that you can run to control both fans. They run about $200.

Again, Formula1LE sells a set up that he charged me $150 for which is stout and runs as I described earlier. I'm only plugging him because he makes a good product and because I believe in supporting the guys here over the big companies.

Ozz1967

iTrader: (4)

That's a good set up. I fall into that last catagory though. I just didn't have want to have to worry about turning the fans on.

RS Chris

^^ I hear ya on not wanting to worry about watching the gauges.

formula1LE

iTrader: (3)

I'm glad your fan kit is performing like you wanted! The biggest decision since my kit uses 2 temp switches is where you plan to install them because placement of them determines what temp range you decide on. Personally I like to use slightly higher temp switches only because I like to give the radiator a chance to shed heat without having the fan(s) kicking on prematurely.

The best part is that there are NO exotic or specialized parts to source after you've installed the harness-everything can be replaced at a good parts store or GM dealer-that's something I designed into it because too often every cooling system company changes their controller design for whatever reason.

What makes my kit different is that it allows you to use ANY fan or dual fan setup as a 3-speed system. Its 100% stand alone and can be used with or without an ECM OBD11 where you need 2 negative trigger fan outputs so there is nothing like it on the market. If you want more info about it, feel free to PM me. I've sold quite a few units over the last year and a half.

Myorangecamaro

I stole one off a 4th gen, fit in great! Made two brackets from aluminum, took about an hour

Ron U.S.M.C.

It is a 14in puller fan that comes on at 160* and is mounted to this cooler then mounted to the inside of the radiator. I put brackets under it to support the weight.
The transmission fluid runs constant through 6, 17in passes all the time and a engine oil cooler that runs through 4, 17in passes at 180*.The front 16in. pusher is just for back up set at 200*
Not the most common set up but one I did during my "learning curve" Both fans are adjustable ,temp. controlled on there own independent circuits. Works very, very, well.
= http://www.summitracing.com/parts/der-15903

formula1LE

iTrader: (3)

This is my latest 3-speed version....its a 2010-up Mustang GT fan assembly powered by my conversion harness. This is slightly larger overall than the Mark VIII fan. Itsbhas a fairly quiet "S" curve blade and moves HUGE amounts of air!

Ron U.S.M.C.

formula1LE ,
I'm always impresses with the quality of your products.
Leaps and bounds above anything I've seen elsewhere and perfect for the serious builder.

formula1LE

iTrader: (3)

Thank you for the kind words! I've always enjoyed modern style upgrades made to appear factory-and I think the R&D put into OEM fans is what makes them so robust.

MY87LT

iTrader: (2)

I'm still trying to figure out the wiring for my dual fan set up. Want to do it right the first time so I'm taking my time and researching everything about the conversion.

Ron U.S.M.C.

Cars with single fans stock are controlled by the switch in the head .Other cars that came with the two fans ,the first is wired to the head but the second is controlled by the ECM. Since yours is Carburated there is no ECM.
My car came with a single fan but I added a second one. I wired it on its own independent circuit. Not a stock set up at all.
Even the first fan does not use the stock wiring any more. Its also independent.


formula1LE , might have something for you.

MY87LT

iTrader: (2)

My car does have an ECM. But you're correct that my single fan set up works on the temp switch on the passenger side head. Eventually going to have both fans come on at the same when the head temp switch kicks them on or when the air con is turned on. I know I'm going to need a second relay which I'm going to locate next to the existing one.

Ozz1967

iTrader: (4)

This is exactly as I have mine set up. I got my set up from *Formula1LE* and the few times I've had it out this winter (only on nice days) it's run flawlessly.

formula1LE

iTrader: (3)

If you want a 2 or even 3 speed dual fan harness, PM me for details about it-the big issue (sometimes) can be the high amperage draw of having the fans kick on @ 100% speed then off again. There's no reason why you can't run virtually any dual fan assembly in 2-speed mode or-if they are especially high powered, 3-speed operation is an option too....and this can all be done with relays.

Ozz1967

iTrader: (4)

Honestly, running it direct from the battery feed hasn't been an issue that I've noticed. Then again, I'll know more come this summer when temps soar into the triple digits and I have my AC cranking rather than the T-tops off. That'll be the real field test.

Ron U.S.M.C.

I stand corrected and is a subject I need to research.

Ozz1967

iTrader: (4)

Hey Ron,

You have it right, you've given him nothing but solid information.

Based on what I think he's saying, his ECM doesn't control his fans at all like some of the other later cars do even on the single fan set ups is all.

MY87LT

iTrader: (2)

Ron has been helpful don't get me wrong. From my understanding the cars that came with dual fans from factory namely the T.P.I. cars have the first fan go on with the temp head switch and the second comes on when the E.C.M. signals it to do so as well as when the A.C. goes on?

Ozz1967

iTrader: (4)

Almost,

The first fan is ECM controlled, the second fan is switch controlled.

However, on some V6 cars and some later single fan V8's, the fan was controlled by the ECM and not a switch as in earlier models.

Ron has his turning on, one fan at a time, at different temps. His system works perfectly fine and is a great set up.

Both of our systems work very well, you just need to decide how you want to do it.

Since you're wasn't ever controlled by ECM, and you want both fans to come on when the switch drops, and you want AC, you need to either run one switch with one temp to turn on both fans at 100%, or you want FORMULA1LE's system that brings them both on at the same time but at two different set temps. His system also has a provision for AC. This is how mine is set up.

If you want one fan to come on at a lower temp and then the second to come on at a higher temp, do Ron's set up. You really can't go wrong either way.

formula1LE

iTrader: (3)

Here's another option I have for ya-this is a dual speed/dual fan assembly controlled by a 3-gang relay bank. This is a stand alone system where both fans move with a low and high speed as well as an AC high speed override. This fan assembly only has 6 leads to run:

Battery power
Switched ignition source
Chassis ground
AC clutch lead (or low pressure switch)
Low temp switch trigger
High temp switch trigger

These fans on high-speed are rated @ approx. 3600-3800 CFM.

Ron U.S.M.C.

See,now that's the ticket and exactly what I would run if I ever decided to tear mine apart. Nice and clean and all on there own independent circuit.
Since my ECM was not programed with the fan option and I was just starting to understand relays and circuits I decided to use a modified circuit I came across.
Both fans are on there own adjustable temperature controlled circuit that looks like this.

Here's the adjustable controllers and probes. Not even in the same league as formula1LE professional circuits but surprisingly effective and dependable. And a photo of the bay just for the heck of it.

formula1LE

iTrader: (3)

Ron, I have no problems with the probe style sensors-in fact, I've used them on quite a few Jeep Grand Cherokees where I swap the junk OEM fan in favor of a 2-speed T-Bird fan. Its just that with GM style temp switches, any parts store stocks them usually. Sometimes, if there's no place to thread a temp switch in, plan B for me is to incorporate a probe style setup. I've used both Hayden and Imperial and never had issues with either. But, I only use the probe style kit to trigger my own relay bank to handle the current draw-most are rated @ 10A which is not enough to power a fan on its own.

Ron U.S.M.C.

Fan amperage is the reason its a ground triggered switch. The only amps going through the controller is coming from that low ignition sorce on the relay ground wire.
Leaving you the opportunity to run whatever high amp fan you want on the power wire coming from the junction block to relay to fan.
I strongly recommend a second back up fan on a circuit either exactly or similar . A duplicate that comes on at a higher temp. and acts as back up incase the temps start to get high or the first fan fails for some reason.
I'm sure you know that but for the sake of those having trouble reading the circuit I posted.
Also if you want to incorporate the A/C circuit they will have to modify or use one of your systems. Mine does not work with the A/C aspect.
It does not show it in the bay area photo but my A/C has been deleted only leaving the heat. That's all I need here. I live in "Wine" country.

formula1LE

iTrader: (3)

The last three of my RamCharger dual fan kits have shipped out this weekend-I'll bebputting a few more together this week so if anybody needs/wants one, drop me an line!

Ron U.S.M.C.

NICE !

Ozz1967

iTrader: (4)

Wow, man those look great!

MY87LT

iTrader: (2)

I began my dual fan conversion today and ran into a problem that I never took into account. The fans are rubbing against the aftermarket three core radiator. Guess I'm going to have to shim the fan brackets and also move a power steering hose a bit.

Ozz1967

iTrader: (4)

On my 84, when I did the conversion, I ran into the same issue, the fans were rubbing on the radiator. I was using the factory 84 radiator. I don't get how a factory fan and fan shroud from an 88 doesn't fit the factory radiator in a car that is built identically but is only a few years older. I even had great pictures and the mounting points are perfect.

JamesC

iTrader: (5)

I'm late to the party, but here's the writeup on my conversion to dual electrics:

https://www.thirdgen.org/forums/cool...electrics.html

JamesC

formula1LE

iTrader: (3)

How deep are the dual fans you're using? The RamCharger assembly is dead on 3" in depth.

MY87LT

iTrader: (2)

The dual fans are from a donor IROC so installation was pretty much straight forward going from my single electric to the dual. But like I mentioned the aftermarket radiator is pushed out more than a factory stock which I never took into account.

MY87LT

iTrader: (2)

Some shims were needed due to my larger core radiator.

MY87LT

iTrader: (2)

Ok done. Finished the installation of the factory dual fans. What I ended up doing to get both fans running was I bought the new replacement dual fan harness from Hawks I believe, and then I cut off the connectors for the relay and the main harness. All I was left then was with the ground and black wire with red which is the power. I spliced both those to my existing single fan connector and both fans kicked on. First I turn the key to on and turned on the A/C and the fans both turned on. Then I let the car run to temp and they both kicked on and are both working as I hoped they would. Nothing shorted out (yet or I hope) and the wires didn't get hot. Just have to clean up the connection I temporarily made and good to go onto the next project.

formula1LE

iTrader: (3)

You should check amp draw to be on the safe side. The GM factory relay I believe is a 30A relay max and I'm willing to bet those fans pull about 25A or so....the sudden surge of coming on 100% from a dead stop will kill that stock relay....I'd suggest at a minimum put each fan on its own relay and trigger them both at the same timenif going this route.

Bddbrd86

https://www.ronfrancis.com/products.asp?dept=87 Here are a few options for fan wiring

MY87LT

iTrader: (2)

Here are two pics of the connection I made to the existing single fan plug and the donor fan motor plug to the fual fan harness.

MY87LT

iTrader: (2)

I've discovered a problem. The fan wires are getting hotter than usual. I searched on the forums here and some say it's due to a motor going bad but I have to rule that one out as the motors have been tested and are fine. The other issue maybe grounding for the fan wiring is not sufficient so that's next on my to do list.