Powerful 12" Pusher Fans

[Trevor]

If any of you out there need pusher fans because you have some crazy turbo(s) behind your radiator there's isn't as many to choose from as pullers. I've been running a set of Spal's pushers for years (rated at 3300 cfm total) and they did OK but when it was 100+F outside and I was in hard core stop and go traffic (or climbed the local mountain in 5th gear) they could only hold the temp at 194-196F but they couldn't drop it.
http://www.spalusa.com/IMAGES_PRODUCT/30102025_XL.JPG


I switched to a pair of Derale 16925's:
http://www.derale.com/basic/default.aspx
http://www.polyperformance.com/shop/images/D/16925-large-400.jpg
They're rated at 4300 cfm for the pair. I really love Spal fans so I was a little worried about this possibly being marketing BS from Derale but I made the jump anyway since these were the best fans I could find (spec wise) that would fit. When I got them out of the box I was happy to see Bosch fan motors on them. After the install let me tell you...these guys work significantly better. Not only does the "hands in front of the IC" test approve the car also cools off noticably quicker once they kick on. The fans operate alot less often (194F on & 183F off). They're not as thick as the old Spals either.

The bad news is they pull some current so you have to build a decent relay/power system to feed them (IE not stock). The good news is they come with relays and thru the core mounting straps right in the box.

[pos-vr4]

did you 86 your AC??

[Trevor]

Yep...it had to exit the building when the IPS single turbo took over the facility.

[Atrosity]

What is your engine temp with these new fans on a hot day?

What kind of radiator do you have?

[Trevor]

What is your engine temp with these new fans on a hot day?

What kind of radiator do you have?
181-195*F

3SX Dual Pass

[SilverJester]

Can you run a pusher fan if you still have A/C? I just like the idea of more room in the engine bay.

[MR2]

Another interesting piece of Trevor news :)

from memory your radiator is slightly smaller in size to fit between the front frame? (push into where the A/C rad was?)

[Trevor]

Can you run a pusher fan if you still have A/C? I just like the idea of more room in the engine bay.
There's absolutely no way you can fit those Spal fans with the AC condenser and I seriously doubt the Derales would fit in there either.

from memory your radiator is slightly smaller in size to fit between the front frame? (push into where the A/C rad was?)
My radiator is an off-the-shelf copy. Nothing special. I have it slid forward as much as I can without modding the mounts or nose sheetmetal (and even then the turbine blanket is still touching the radiator).

[MR2]

mmm ok interesting! very much up for what all the guys that do serious tracking with serious power are doing mod wise to keep the temps in line.

[TurboSinceBirth]

I had to modify my FALs so my front turbo would clear and I know they won't be up to the task. I was going to get some stock fans but I may have to give these a shot if they'll fit in front of my radiator. How did you wire them up to the AEM Trevor?

[Trevor]

I picked up the stock rad fan relay's switched power and ground that the AEM controls right at the fuse box behind the passenger headlight. Split it and ran it to the two seperate relays...one for each fan.

[cjbyron]

Nice info Trevor. I've got the 94 single setup wired up the same way for the high amps. Was considering looking at trying some other fans as we've got the front pull apart for winter changes. It holds okay but on really hot days can climb at idle. Maybe I'll try grab some of these to try. Sounds like you like em.
Thx.

[Broomfield Racing]

I bought one of these under your recommendation. Thing is freaking awesome, pushes A LOT of air. Also draws a lot of power, my lights dim at night when it kicks on. I also wired my aem to the relay. I run 1 pusher and 1 puller now and the car stays nice and cool. Reason I bought one was the stock puller wouldn't fit between radiator and turbo. I may run a switch to override the temp sensor so that the initial draw of power doesn't take anything away from the fuel pumps during a pull. Thanks Trevor.

[cjbyron]

I bought one of these under your recommendation. Thing is freaking awesome, pushes A LOT of air. Also draws a lot of power, my lights dim at night when it kicks on. I also wired my aem to the relay. I run 1 pusher and 1 puller now and the car stays nice and cool. Reason I bought one was the stock puller wouldn't fit between radiator and turbo. I may run a switch to override the temp sensor so that the initial draw of power doesn't take anything away from the fuel pumps during a pull. Thanks Trevor.

I'll try two to replace the pushers I'm using now. Not too worried about a surge affecting other equipment because any line needing that much power (~50A) needs it's own feed right from battery anyway IMO. But no doubt these high of draws need consideration in setting up their supply.

So you're using an AEM LS to turn them both on/off right? That's currently how I have it but was thinking of splitting them using two different LS's (more like stock). If these really push that much air then having a low/high might be beneficial too. Also from a surge perspective. If one fan will keep me below 200-210F then no reason to have another 20A+ one running untill needed.

Don't know that I'd want to use the temp sensor as the on/off signal with a switch though. Maybe just use different parameters to meet the surge during a pull that you want to address? Or shut one down under a set of parameters? Sort of like shutting them down over 50mph. Same process.

[Broomfield Racing]

It wouldn't be an issue if I had a bigger battery haha. A switch will do fine, flick it before I make a pass. Works perfect on the street as is.

[cjbyron]

One thing I noticed on these as they come from the mfg'er - the fuse system is inferior IMO. For the amount of current these are rated to pull I'd not trust the fuse holder that comes pre-wired to the relays. Those cheap type of holders are well known for overheating/melting on high loads. Low quality and should be replaced with higher grade like a maxi-fuse or equiv.

[Trevor]

I have the low side from the AEM running the relays. I didn't use the fuses the fans came with...both relays have a seperate power feeds & fuses off of the aftermarket fuse box I have.

It's worth a try running the fans from two seprate low sides from the AEM. The only issues that kept me from doing is there is only one radiator fan otput template so the second fan would have to run as a normal output (IE where it's on above 195F and off below 195F (both the same temp)) and I think one fan in the local 100+F heat is only going to delay the inevitable...both fans will always ultimately need to come on to drop the temp back down. I bet that first fan is going to be running near constantly when it's really hot around here. I'd rather just cut to the chase and have both fans tied together if one fan isn't going to cut it.

[cjbyron]

LS2 is normally setup for Fan2 under the output config. LS9 is setup in the same config but under functions rather than outputs. But in reality they are both just low side outputs. Pins 20,20 on 94+. That’s how they come in the AEM. You can of course assign whatever LS you want.

Using the one single LS (as setup in the stock config) will overrun the current capability of the stock relay. It is only rated to 20 amps. Each fan needs its own 30A circuit. So to run both fans and prevent electrical overheating and to accommodate surge amps you need a circuit capable of 60A. Even one of these fans exceeds the amperage of either of the single circuits (relays) as wired in the stock configuration. Good to have that aftermarket fuse system right! :)

I tried running both at same time previously on old setup but saving 20A+ of electrical consumption if not needed by running both LS circuits worked out best for me. Why consume that much power if not needed was my opinion. Plus by having them on at different times using the 2 LS controls also prevents a ~45A+ power surge on electrical system. Then again, you are in AZ and I am in WA so we have some difference in ambient summer temps I’d say. LOL.

In addition to all that, the stock fan relay could not provide more than 20A without overheating when I tested it. It also had a ~2V drop in supplied voltage when under load when I ran the tests (on 2 FAL fans pulling approx. 23A). That voltage drop is totally unacceptable to me. The testing is what led me to rewire the fan configuration entirely and ultimately change out the fans entirely too.

[Trevor]

(At least on the S1 AEM ECU) There is only one "Rad Fan" function that LS9 usually points to. LS2 only has "Basic Activation" control and does not have a seperate "fan2" function - or - "fan on above XXX*F"/"fan off below XXX*F". Since that's the case you only have one temp to play with on LS2 and you won't have a buffer...it'll be on above that one temp and switch off below that same temp. Since that's the case when it's cool enough outside for that one fan to manage the temp that single fan will constantly cycle as it attempts to hold the temp at a single temp (IE 185F) instead of the range you get with the "Rad Fan" function. Not the best idea for OEM reliability for the power control system for that fan.

I don't use the stock relays or any part of the stock power supply system for the fans and the current draw from both coming on at once doesn't cause any issues whatsoever. Maybe it's because I've upgraded the power & ground from/to the alternator but the voltage regulator picks up the load very quickly. There are alot of factory vehicle that utilize a single high current (60+A) fan to manage the coolant temp. Using the fans as a pair is no different in my mind.

[cjbyron]

On 94+ section of (yes, AEM S1) you'll see that just like stock there are two fan controlling LS's. It is that way because that's the stock configuration too (both fans are controlled independantly). No idea why you think there's just one fan LS. Perhaps it is just confusion over terms. LS2 is for Fan #2 (high fan) and is in config/output, LS9 is the passenger side (#1) fan control. They are just in different places in the setup (config options) drop down and #2 is just not labeled "fan" but that is it's function. Each is also noted as such by AEM.

I understand what you are saying about the buffer but iirc it does enable a 4degree buffer on LS2. There's some added info from AEM on how those work together. It's also how I use it on my semi-stock blue 95 and there's no cycling or problems at all with running the way the AEM is setup out of the box. Either way, the AEM is just like the OEM box that way; two outputs that pull to ground for each of the two fans. LS2 and LS9. That matches the OEM way of doing it and is why AEM setup the 1311 box that way.

Of course you can use LS9 for both easy enough. Either / or. I have switched to running the two separate LS controls and prefer that for various reasons now. Mostly after testing V drops and feed requirements (and I have an entirely rewired vehicle just for supplies as well). I also don't need two 2200cfm fans on 100% of the time as my temps stay very stable. it's only on a 90+ day and doing hard running (WOT) that the high fan is needed. So for my needs it is best to run (2) LS. Since your in AZ and seem to have overheating at times then both all the time works for you it sounds like. Whatever works is what's best for the individual.

The reason I pointed out the poor fuse holder is also for other viewers that might buy these fans in the future from this thread. Since the thread sits here for others to read it's always good to have accurate or alternate info that can be applied to each individuals needs or preferences.

[Trevor]

I'm shaking my head here.

I don't think you quite understand what I'm saying...while you can point both the LS9 and LS2 ouputs at the "Rad Fan" function on my version of AEM Pro (3.23r9) there is only one "Rad Fan" setting which is common to all outputs that reference that function. You can not set LS2 and LS9 activate at two seperate temps based on pointing at the "Rad Fan" function alone. If you open LS2, flip to the function tab, change the on/off temps for the "rad fan" function to off the wall numbers, then open LS9, the function tab, and check those same temps you will see those same off the wall numbers you punched in while under LS2. Test it...they're tied together and they are not seperate.

About the only way you can have them both pointed to the "Rad Fan" but then behave even slightly differently is by setting one of the LS's to go active in the middle of the "Rad Fan" range. Example:

LS2 (Low temp):
Active - 158F (or whatever </= 183F)
Off Below - 183F
On Above - 194F

LS9 (High Temp)
Active - 189F
Off Below - 183F
On Above - 194F

Both fans will still initially turn on togther at 194F. Once the temps start dropping LS9 will deactivate at 189F and LS2 will only deactivate below 183F. If LS2 can't drop the temp solo and it creeps up above 189F again then LS9 will activate seperately (just like you're after).

Now ya get me? Now if I missed something I'm all ears. What are your settings to get them to activate initially at two seperate temps? My guess is while both of your LS's have "Rad Fan" checked one of your fans isn't set to go active until above the Rad Fan "on Above" temp and is therefore operating without a true buffer; and as such the Rad Fan function isn't doing jack for that output and can be disabled.

[cjbyron]

I shake my head along with you (WTF?)

Yes, I KNOW there is only the one function "rad fan" function. It's sort of right there in the program. I'm not new to AEM.

All I was saying is that under the stock setup for the AEM there are two separate LS controls for the two fans. Not just one. And yes, only one of them enables the "rad fan" function in the lower screen. All you have to do is look at the stock startup map to see that only one fan has that enabled but has a different "at least" in the temps. There is ony the one setting for off below (function) but the on above is similar in the LS settings by being the "at least" setting.

Or perhaps we are saying the same thing. It isn't "my" settings but instead I reverted BACK to the stock style settings which does indeed turn the two fans on/off at different settings. AEM calls them radiator high and radiator low (pins 20 and 21).

If you open a stock startup map you'll see what I mean. The two fans do not operate together but come on with their own controls (ex: like the high fan coming on with the AC call).

[R/T93]

You guys are AEM dorks.