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E-fan: push or pull?

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Old Apr 26, 2006 | 08:24 PM
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E-fan: push or pull?

I just bought a Derale e-fan to use in my 87 TII for hella cheap. Question is, should I use it to push or pull? I will have my FMIC on here pretty soon, mounting them both at the same time. The FMIC is almost 3" thick and the fan is 3 3/4" thick 16" diameter. What would you do, mount it in the typical location or between the radiator and the FMIC?
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Old Apr 26, 2006 | 08:29 PM
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I'd mount it in the typical location
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Old Apr 26, 2006 | 08:32 PM
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pull
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Old Apr 26, 2006 | 08:38 PM
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Pull.
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Old Apr 26, 2006 | 08:57 PM
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It would pull air, through the IC and push it through the radiator...
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Old Apr 26, 2006 | 09:02 PM
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no put it on the back side of the rad so it pulls through both
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Old Apr 27, 2006 | 12:22 AM
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yah, I think that's what I'll do, just mount it on the radiator.
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Old Apr 27, 2006 | 02:17 AM
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yea mount it on the rad to pull both...besides with the oil cooler where the hell would you mount it inbetween them?
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Old Apr 27, 2006 | 02:47 AM
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puller fans are much more effective than pusher fans, mount it behind the radiator where the stock thermo fan used to be.
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Old Apr 27, 2006 | 03:00 AM
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Originally Posted by Karack
puller fans are much more effective than pusher fans, mount it behind the radiator where the stock thermo fan used to be.
Haha, "behind" the rad. could mean two different things depending on how you look at it... Behind as in, behind the rad. looking at the car from the front, or behind the radiator from the engine-bay.

Regardless, isn't the little stock E-fan a "pusher"? Like, it "pushes" air through the Rad?
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Old Apr 27, 2006 | 03:09 AM
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i dont think theres a car in the world with a fan that pushes air through the radiator
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Old Apr 27, 2006 | 03:18 AM
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i meant the thermo clutch fan you dork.
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Old Apr 27, 2006 | 03:22 AM
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Originally Posted by Mint87RX7
i dont think theres a car in the world with a fan that pushes air through the radiator
NO but there are a couple trucks I can think of.
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Old Apr 27, 2006 | 03:24 AM
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only use a pusher fan if there is no room for a puller, that is the ONLY reason to use a pusher.
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Old Apr 27, 2006 | 08:01 AM
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Originally Posted by Mint87RX7
i dont think theres a car in the world with a fan that pushes air through the radiator
BMW?
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Old Apr 27, 2006 | 08:54 AM
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Originally Posted by Karack
only use a pusher fan if there is no room for a puller, that is the ONLY reason to use a pusher.
I use a pusher for this reason in my VMIC setup (although I would much prefer pullers).
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Old Apr 27, 2006 | 08:59 AM
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Definately pull.. Make sure you wire it up to pull if you mount it behind the rad. I crossed my wires and had it push when I installed it and it almost spelled disaster...
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Old Apr 27, 2006 | 12:26 PM
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ok guys, after looking at the car, there wouldn't even be enough room to even put it in the front cause the OC is in the way. so it getting mounted on engine bay side as a puller.

now another question, am I going to need to make a shroud? fan flows 1600 CFM.
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Old Apr 27, 2006 | 12:36 PM
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how much power can you recover with a e-fan and with the clutch fan removed.( i say recover because the clutch fan basicly robs power)
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Old Apr 27, 2006 | 12:44 PM
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Originally Posted by raksj04
how much power can you recover with a e-fan and with the clutch fan removed.( i say recover because the clutch fan basicly robs power)
some, but nothing really noticeable. I went with this e-fan cause A, $130 unit I got for $10, B, I like having a nice open engine bay.
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Old Apr 27, 2006 | 12:45 PM
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Originally Posted by raksj04
how much power can you recover with a e-fan and with the clutch fan removed.( i say recover because the clutch fan basicly robs power)
Common myth, trivial gains which are negated by the strain of powering it. Stock fan cools better then e-fan no matter what. If you dont have to put one, DONT.

Clutch fan is only used when you stop anyways, so whats the point in freeing up hp at idle !!?>?!!?!?!!
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Old Apr 27, 2006 | 01:07 PM
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Originally Posted by raksj04
how much power can you recover with a e-fan and with the clutch fan removed.( i say recover because the clutch fan basicly robs power)

Ive seen as much as 4% (on dyno's) But the more power you make the smaller percentage its going to be. But below 250 I would call it 3% to be safe.
(i got 1hp on my old nissan hardbody)

The major benefit of an electric fan is (also true for an EL waterpump.)
- it pulls a steady CFM
- you can have it cycle (on and off), this helps maintain a steady coolant temp with smaller fluctuation

In order to get the most from an EL fan you must make a cowl for it, as in a "ring" that sits as close to the edge of the blades as possible. If you just have spinning blades with no cowl you operate at 23% (so im told) of the potential of the fan.

Mathematically push or pull CFM IS CFM so as long as your ducting is proper, there should be no difference.

You only really need a cooling fan below 5 mph In the FC's since we have a large inlet I doubt a CF does much good at speed, Anyone who has a Thermostat controlled CF knows that its rarely on while the cars in motion, but most always turns on while at a stop with the AC running.

For instance If your road racing and you are overheating, All the cooling fans in the world will do you no good you simply need better radiator,wp ect.

Personally Im a big FAN (punny...) of a pusher as it leaves the engine bay free of clutter and one less thing to seriously injure people that have no business being in an engine bay in the first place.




Last edited by ajhehr; Apr 27, 2006 at 01:16 PM.
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Old Apr 27, 2006 | 01:37 PM
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^Now that is some sexy ducting!!!!!!!!!

Now here is a Q for the thread starter. The E-fan you got. What's the CFM?
I've seen those fans and they have a few different cfm 16 inch fans.

You need 2500+cfm

Pullers are easier on our cars because fo the room and access.
Ducting is a HUGE part most people miss.

You need a shroud which will cover the entire radiator and you need to make sure there are no gaps ahead of the radiator. Gaps will give the air a path to go instead of through the radiator.
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Old Apr 27, 2006 | 02:43 PM
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the fan flows at 1600 CFM.
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Old Apr 27, 2006 | 03:08 PM
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Junkyard fan FTW.

then just go to home depot and fashion yourself some brackets.

the power gain is minimal but I feel its better throttle response, not to mention it cleans up the engine bay hella alot.

Last edited by fidelity101; Apr 27, 2006 at 03:11 PM.
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