[RESOLVED] Four 10" fans. How to wire them.

[Icarus]

So I have 4 10" fans. I have them mounted but I need some opinions on how to run them. I was originally thinking front pushers fans linked to AC and rear puller fans linked to the Rad switch. But then I was thinking maybe I should wire them like the stock system, right/left, instead front/back. Anyone see any advantages to either setup.

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Preemptive counter-cynisism:

1. Why 4 fans? I have a 40x10x3 FMIC, doesn't leave much room for air flow to the intact AC/Rad.

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2. I know I forgot to flip the blades on the pushers, I was in a rush.

3. Why not use 2 large puller fans? I want the most airflow for the smallest footprint on the engine side, more room for fun stuff.

 

[BoostedTalonTS]

^^^ -You forgot one...


4) Why am I mounting 4 10" fans on a stock radiator, with AC still intact?

(I tried doing that with a much smaller FMIC core and it would start to overheat with the AC being on for ~5 minutes. Come to find out (as many before me did) that the FMIC, AC condenser, and a stock radiator isn't a good combo... I even tried wiring up the OEM AC fan to come on with the ignition... No go... Got a Fluidyne radiator. -Problem solved. -I don't know if putting 4 fans in there (2 push, 2 pull vs 2 larger pullers) would truely be of any bennefit.

Bottom line: if you want a big FMIC & AC (that you can actually use for more then a few minutes), you will need a larger radiator... Might as well do that now.

 

[Rob10_99]

+1 but I live in AZ where its almost needed if you have AC.
It doesnt even get 80+ in seattle does it? !
I would have one fan on( stock location ) all the time, and have the AC fan on when the ac is on.
The front two would be on the thermistor switch, sound reasonable?
yeah and fix those directions before you overheat =)

Just an afterthought, you live in washington state, when do you use your AC? like 2 weeks out of the year?
Im totally being serious because I moved from oregon almost a year ago.

 

[Icarus]

Thanks all for the input so far.

1. Full cooling system upgrade is on the list, hoses and 2" aluminum radiator. I guess I will have to wait and see how the weather treats me. That way I can justify the expenditure to my Fiance
2. I was thinking about having the front set switched via relay from a thermistor placed below the inlet. This way it could activate all 4 if things got toasty.
3. I'm from Eastern WA, It's sage brush, tumbleweed and hot summers. I'm still over there on a semi-regular basis.

Any other have thoughts on left/right, front/back?

 

[Defiant]

Discard two of them. They won't help any.

 

[bmoha2]

I guess that would vary per fan and setup I have a manual switch wired into my double din filler panel that I flip on under 45 mph with two puller fans

 

[slugsgomoo]

ditch the two pushers, build ducting between the fmic & radiator so that you maintain flow, and build a shroud for the puller fans.

if you can fit either of them, i'd run a stocker and a slimline (or two stockers if possible) even though they don't look as nifty. Stock fans move a TON of air compared to slimlines.

 

[99gst_racer]

Honestly, I don't agree with needing 4 fans.

With a 24"x12" radiator core on a DSM, two 12" fans will cover more surface area than four 10" fans. Not to mention, two 12" fans probably produce as much or more CFM than four 10" fans.

 

[Gamble97]

2 Spal fans is all you need. And if you want to wire all 4 of them you will need to wire 2 of them with a switch. No way could you do 4 fans on stock wiring, it's way to much current. IMO.

 

[steve]

No way could you do 4 fans on stock wiring, it's way to much current. IMO.

Yep, That's what relays are for.

 

[illeffekt vr-4]

I think 4 fans is overkill. You could of gotten away with a 14" puller on the engine side and a smaller fan in the front acting as a pusher.
The two pusher fans in the front will help while stopped for a long time in traffic but at highway speeds they will block some of the flow to the radiator.

 

[Icarus]

There are some issues with IC piping that requires needing room on the engine side bottom of the radiator. That's why I chose 10" fans. I knew 2 10" fans wouldn't move enough air so I was hoping 4 would do the job. From reading threads on the subject I believe the stock fans are rated at 1400-1500CFM each of these is rated at 1250CFM putting me a bit shy running only 2 in addition to the added restriction of the FMIC. I also made the fake holes at the top bumper cover into real holes giving me to allow some unrestricted air through to the radiator.

As I stated earlier, I was planning on running a relay to activate 4. The relay would be switched via a thermistor placed below the inlet in the radiator. From what I've read, the radiator relay will not activate the AC fan; where as th AC relay activates both the radiator and AC fans. This is why I want to set up an aftermarket temp activated relay at ~210* to activate the other 2 not switched by the radiator relay, not all four on the radiator relay.

I will give the 4x10" fans a try and if I find that I have cooling problems I will upgrade to a 2" aluminum radiator. If that still doesn't cut I will look into some 12" puller fans.

Thanks for the input on the choice of mounting, I was hoping someone would have an opinion on whether to go left/right or front/back.

 

[andy4g63]

4 fans, it is a overkill. I've seen a guy with same set-up and he still was running hot.
Check Perma-Cool 12" High performance fan. It is rated at 3000CFM's. Put a 10" in front of rad. You might want to build a shroud around the Perma-Cool fan, cause it does not have any. That is all you 'll need. Build a ducting around FMIC and call it a day.

 

[Icarus]

Anyone know of a good reason why I should leave the resistor from the AC fan and is there location that it should be mounted<=(My son wanted me to use a smiley)

Edit: I found what I was looking for after couple searches, thanks.

 

[GORBS88]

There is absolutley NO point in running 4 fans, Run 2 fans as pullers wether they are 12's or 10's but don't put any infront. MOST fans move more air in the puller form so by putting a pusher infront of it, the pusher will actually hinder the air flow as the pullers can't pull the air they need to. Same senario as driving down the highway with the fan on, which will also SLOW the air that would be pushed thru the rad.

 

[bmoha2]

45mph approx depending on the fan

 

[twicks69]

#1: Please tell me you are going to be running a turbo much larger than the one you currently have. If not, that intercooler is complete overkill and will hurt you more than anything else.

#2: 4 fans are a complete waste unless you are pulling the AC, doing ducting, installing a vented hood and doing heavy duty road-racing. Ditch two, and have them wired up with a relay switch from the Rad Fan harness, and install a 185 degree thermostat. The fans kept would be used as a pusher/puller on the passenger side of the radiator to give extra clearance for a future turbo setup.

#3: Do not get too greedy and place too large of an aftermarket radiator in the car; You are better off with the large/thin stock core for expelling heat quickly if this car is just a street driver. If you are road-racing, then you are justified to use a 2" aluminum radiator.


FYI: I am running a PTE Large FMIC, one 12" Spal fan as a puller on the passenger side and a stock radiator with a 185 degree thermostat and a 1.3 bar rad cap along with the A/C condensor removed, and a little front bumper and bumper plastic support cutting. I have never had cooling issues, and have never seen above 195-200 degrees even in summers at the race track. Your setup is extreme overkill for a drag racer or street car.

This setup has handled over 1000HP without cooling issues. Even in 90-degree weather when I am frying like an egg on my black leather interior.

Just trying to save you some money by going the "minimalist" route vs. the "overkill" route.

Good luck,

 

[Icarus]

Thanks, everybody for you input. I was mostly looking for opinions on wiring left/right or front/back. Here's my reasoning and what I've decided to do.

Reasoning:
1. As I stated before because of IC pipe routing I need a smaller fan radiator side.
2. The fans I already purchased are fairly inexpensive and because of this I have factored in a large tolerance for the possibility that they do not flow as much as rated.
3. Because of limiting factors, money, my available time and primarily needing my car running again, I will not be fabbing any ducting or buying different fans.
4. I realize that with my current setup this much cooling and intercooling is overkill. I paid $86 shipped for the intercooler which appears to be a one-off custom, described being for a WRX, by a company called ADFX. It was cheap I like how ArcticTSI's R32 FMIC wrapped around the side rather needing additional bends and couplers like typical large cross-flow IC's. This is why I got this particular IC. I'm looking to the future and would rather do overkill than upgrade twice.

How I wired the fans:
I went ahead and wired the fans back/puller=switched by rad relay, front/pusher=switched by AC relay. I will be ordering a thermistor and relay for the front fans as a backup in case the radiator fans need help this summer. If I run into problems I will follow-up and post any troubles I encounter. For $90 shipped, a theoretical combined flow of 4900CFM and a very small footprint that allows the retention of the AC, stock PS cooler location (with some bending) and fairly large IC, this may be an excellent budget upgrade for people with cooling issues. I guess I'll find out...

 

[twicks69]

That will work, but I am hoping that your 4900cfm fans pull anywhere near that concerning that the incoming air volume will be reduced by the flow restrictions of the IC and A/C condensor.

Good luck, and I look forward to hearing your results.

 

[Icarus]

So I F'd up!!!

I was waiting for the thermistor to get the front fans included. The weather has finally warmed up, 80's and my car overheated yesterday. Well I've been selling my Fiance's cars so she could get this 99 Beetle that she wanted. So this morning in order to get everything done in time, I had to get get up after almost no sleep, I work graves. So I was just going to throw in a SPDT relay and call it good. This was the plan

30. Black slimline fan wire (pusher)
85. Jumper to (+) stock rad fan harness
86. Ground to chassis
87. Batt (+)
87a. (+) stock AC fan harness

The guy I sold a 92 Diamante the day before for $600, showed up at my house wondering why the cruise HC was too high to pass emissions. I was brain dead I could hardly think. I wanted to say hey you talked down the price, it's a $600 car in decent shape that had hundreds put in to it recently, what do you expect from me. I did some troubleshooting with him, suggested the fpr and handed him a 2g maf to hack so he could lean things out.

Now I was late and even more brain dead, I rushed the relay install and cut corners. Well I got in the car, had to do a few things before I checked out the beetle and my car starts overheating. When I stop the overflow is spewing all over the place. Neither sets of fans is working. I check the rad fan fuse, gone. I'm no where near a parts store and have to drive 30 miles in rush-hour traffic to check the beetle out. I swap in the ABS fuse (60amp). I do a quick rewire, sans relay, to get the fans working. Drive another 3 miles still nothing, check it again and something happened, blew the 60amp fuse. Guess what it did to the AC harness which, it turns out, was the problem. So I grab some melted wire strip it and shove it in the hole in the fuse and put the cover back on. Looking back I should've told my fiance that getting this car was not worth killing my car, but I guess I like her a lot. So the back fans are working but I'm still over heating in the bad traffic. 1 hour late and only half way there, I pull over agan to cool down. I deceide I need to have the front fans. So I take what few unmelted wires from the relay I had and wire the front fans directly to the battery so they are on until I unbolt the wire from the battery that pretty much solves it. This is about the stupidest thing I have ever done to a car, including spending $500 on stereo equpiment for a 80 AMC Eagle. I finally make it and get her the car, while I didn't do it for the grattitude, I am hoping for some damn fine "grattitude" in the next 24 hours.

Point being all 4 fans are necessary for weather in the 80s. I don't know about when it gets hotter. Ducting, larger fans or 2" radiator may be on the list in the 30 days, (Wish I could get a nice vented CF hood ala Mavisky). Hopefully I didn't do any permanent damage to my car I'm goign to have to junkyard the AC harness that's for sure. Temp was never more than 1/8" from upper normal limit, but I do worry about warpage and HG issues that may arise.

 

[GORBS88]

So I F'd up!!!

I was waiting for the thermistor to get the front fans included. The weather has finally warmed up, 80's and my car overheated yesterday. Well I've been selling my Fiance's cars so she could get this 99 Beetle that she wanted. So this morning in order to get everything done in time, I had to get get up after almost no sleep, I work graves. So I was just going to throw in a SPDT relay and call it good. This was the plan

30. Black slimline fan wire (pusher)
85. Jumper to (+) stock rad fan harness
86. Ground to chassis
87. Batt (+)
87a. (+) stock AC fan harness

The guy I sold a 92 Diamante the day before for $600, showed up at my house wondering why the cruise HC was too high to pass emissions. I was brain dead I could hardly think. I wanted to say hey you talked down the price, it's a $600 car in decent shape that had hundreds put in to it recently, what do you expect from me. I did some troubleshooting with him, suggested the fpr and handed him a 2g maf to hack so he could lean things out.

Now I was late and even more brain dead, I rushed the relay install and cut corners. Well I got in the car, had to do a few things before I checked out the beetle and my car starts overheating. When I stop the overflow is spewing all over the place. Neither sets of fans is working. I check the rad fan fuse, gone. I'm no where near a parts store and have to drive 30 miles in rush-hour traffic to check the beetle out. I swap in the ABS fuse (60amp). I do a quick rewire, sans relay, to get the fans working. Drive another 3 miles still nothing, check it again and something happened, blew the 60amp fuse. Guess what it did to the AC harness which, it turns out, was the problem. So I grab some melted wire strip it and shove it in the hole in the fuse and put the cover back on. Looking back I should've told my fiance that getting this car was not worth killing my car, but I guess I like her a lot. So the back fans are working but I'm still over heating in the bad traffic. 1 hour late and only half way there, I pull over agan to cool down. I deceide I need to have the front fans. So I take what few unmelted wires from the relay I had and wire the front fans directly to the battery so they are on until I unbolt the wire from the battery that pretty much solves it. This is about the stupidest thing I have ever done to a car, including spending $500 on stereo equpiment for a 80 AMC Eagle. I finally make it and get her the car, while I didn't do it for the grattitude, I am hoping for some damn fine "grattitude" in the next 24 hours.

Point being all 4 fans are necessary for weather in the 80s. I don't know about when it gets hotter. Ducting, larger fans or 2" radiator may be on the list in the 30 days, (Wish I could get a nice vented CF hood ala Mavisky). Hopefully I didn't do any permanent damage to my car I'm goign to have to junkyard the AC harness that's for sure. Temp was never more than 1/8" from upper normal limit, but I do worry about warpage and HG issues that may arise.

Well that sounds like one real bad day to me, BUT. There is no need to have to run that many fans.
I live in the SEMI DESERT and see 100 + degree temps and i have NEVER had problems with a big front mount and all. I run ONE 12 inch puller fan and thats all.
All im saying is there must be somthing else going on that you need to run that many fans. Mabe the HG was on its way out already?
Good luck

 

[Tsi_User]

Before you start cutting up your hood, find out what the problem is with your cooling system. Like many other people have said in this thread, there is no reason to run 4 10-inch fans like that. There are other prople running huge cores and dont need 4 fans to keep from overheating, so something is off. I would try a better radiator.

 

[Icarus]

I hope it's not the HG. The cooling system worked flawlessly before the IC install. My MBC is set to 12-13, with spikes to 14 and only I'm only on it a few times a week. I don't know how it would've gone except for age. I mean it would be a great time to do ARPs and maybe a cometic, timing belt and other stuff, but I'm hoping it's something simple. T-stat is about 6 mo. old, so rad cap would be the next step.

There is a distinct possibility that the fans suck and I don't mean air. With the pushers on by themselves I can feel the a decent amount of air making it through. Another possibility is that the pullers don't cover enough of the radiator core. Which could be the reason why a 12" would do a far better job.

Thanks, for the input. I will continue to update until the problem is solved and a final conclusion on whether a cheap 4x10 fan setup really flows as much as it should.

 

[illeffekt vr-4]

I've said before and I will say it again " do it right the first time and save in the long run".
In your case it would of probably been better/cheaper/easier just to get get the intercooler piping modified than to get so many fans and run into trouble.

Like many others mentioned in this thread....there's no need for 4 fans on a dsm. Hell..there's no need for 3 fans. Most people out there run ONE fan if there's no A/C on the car. If you do have A/C TWO fans is the most you'll ever need.

I went to a DSM meet yesterday and saw several dsms with A/C and huge front mounts running just two 12" fans with no issues. One in the engine bay on the passenger side as a puller and one in front of the A/C condenser on the driver's side as a pusher.

Hopefully you didn't mess up anything while it overheated.

 

[b00stedtalon2]

I simply run 1 stock radiator fan, with a fmic that is just as big as yours. I haven't over heated once.