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Discussion Starter · #1 ·
I am going to have to ditch the 1j hydo fan setup due to clearence issuses with the new radiator and IC piping. I have to go with a electric setup, which I don't like but really have no other choice. I have already decided I'm not going to use the crappy wiring and themator that comes with them, but I going to wire it like Toyota does all there other electronic fans by using a temp sensor. Luckly the koyo radiator has a perfect spot for one(orignally used for the jza70 temp switch) A camry sensor should work perfect here. My main question is do I want a puller or pusher fan? I'm assumeing puller right? Don't want to blow the air onto the IC..Thanks
 
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Since I doubt you can actually mount suitably large pusher fans, pullers will work almost as good (everything else being equal).

You weren't thinking of blowing out, from inside the engine bay out, were you? Hope not. From my testing, fans provide additional cooling up to approximately 80 km/h.

Do you know what electric fans you're going with?

Either way, as with any fan, make sure it's completely sealed to the radiator with a proper shroud. And if you're going with an aftermarket "low profile" setup, you'll need to space it out, as the fans aerodynamicaly stall (flex-a-lites duals, are really bad for this).

Just out of curiosity, what temperatures does the Camry switch activate/deactivate, and from what year is it?

Best Luck.......Sdude.
 
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Bishop92T said:
You want a puller type, they are ~25% more efficient then a pusher. Most electric fans can just be turned around and function as either.
Where did you get that figure of 25% Bishop?

Whatever the source, it is incorect.

Cheers......Sdude.
 

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Discussion Starter · #7 ·
I'm not 100% sure on the temp of the fan switch for the camry, but I can find out tomorrow. I'm copying toyota exactly on the wiring, using the same type of relay as well. It is setup to control ground, and the temp switch breaks the relay when it is actvated. It is designed so if either the switch or wiring to it go bad, the fans will by default work. Basicly if you unplug the temp switch, the fans will come on. I've been debating either the SPAL or the flex-a-lite, but past experiences lead me away from flexalite, although it was their crappy temp sensor that went bad.
 
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Larry_A said:

I don't recall the %age I've seen in the past, but I'm pretty sure their efficiency loss is greater than 25%. Which way do you have it?
:)
A little elobaration.

An axial fan ("normal fan type"), will "push" or "pull" exactly the same amount of air, as long as it doesn't go into "stall" (it goes easier into stall while pulling).

An identical fan, mounted to an identicall radiator, will flow the same volume of air, either pushing or pulling.

HOWEVER.

Once the radiator heats up (normal operation), the puller has less dense air at it's inlet, and will flow less air volume than a pusher fan in the same situation.


Some good information online is at:

http://www.comairrotron.com/notes.html


But I got stacks of books on the subject (plus lots of testing experience), so feel free to ask, if you don't find it at the website link.

Cheers......Sdude.
 

· This Is Why I'm Hot.....
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toypro said:
I am going to have to ditch the 1j hydo fan setup due to clearence issuses with the new radiator and IC piping. I have to go with a electric setup, which I don't like but really have no other choice. I have already decided I'm not going to use the crappy wiring and themator that comes with them, but I going to wire it like Toyota does all there other electronic fans by using a temp sensor. Luckly the koyo radiator has a perfect spot for one(orignally used for the jza70 temp switch) A camry sensor should work perfect here. My main question is do I want a puller or pusher fan? I'm assumeing puller right? Don't want to blow the air onto the IC..Thanks
Hi Eric,
Ouch. I'm sorry to have been the one instrumental in this new conundrum that's befallen you. I pray that you are able to view the issue in terms of ROI. Much like the babe of your dreams requiring more work to keep her yours, the beauty of the radiator will [hopefully] make the effort seem worthwhile. FWIW, I just don't see cooling issues happening w/this rad, regardless of how you plan to cool it.

I used a 14" PermaCool [pull] in conjunction w/the 1-fan aux. Is Death Valley a good enough test for you? We know that trip runs thru the most grueling temperature zone in North America.

I just got a used 2-fan unit to replace the single aux on there now. Heh, one's broken, so I have to swap my single into it, & my shroud will have to go. Dang, it's only a couple yrs old. If you nd it, LMK, you can have it. I'll run shroudless & see how it goes. If it acts up, I'll make something up out of alum sheet metal.

My oldest just belched @ his mother in response to a question. Escuse me while I go kick his a$$.
 

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Discussion Starter · #10 ·
Trust me Larry, not a big deal at all. Although I like the hydro 1j setup, I will gladly ditch it for the koyo. The hydro setup doesn't work as designed due to swapping it in the ma70, since you use the 7m engine bay harness to control the AC, you leave the 1jz engine harness ac unplugged, which makes the fan ecu think the AC is on all the time, and the fan will only run full blast. Which isn't really a bad thing..But I think my design for wiring in the electric will work just fine and better than any of the crap that comes with the elec fans. If it works as planned, no reason it shouldn't, I would recommend anyone with a koyo wire in the elec fans like this, since there is already a perfect spot for the temp sensor. An aftermarket elec. fan temp sensor cost me an engine once...
 

· Dr Wheelspin Rh.D.
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Where did you get that figure of 25% Bishop?

Whatever the source, it is incorect.
I saw some old flow charts, I forget where. Once you get up to speed a fan in front of the radiator will only be a restriction no matter if it's on or not. A fan behind will be much less of a restriction. We're talking real world results here, not results from a laboratory. How about some proof from your argument? :)
 

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Bishop92T said:


I saw some old flow charts, I forget where. Once you get up to speed a fan in front of the radiator will only be a restriction no matter if it's on or not. A fan behind will be much less of a restriction. We're talking real world results here, not results from a laboratory. How about some proof from your argument? :)
Hi Alan,
That's exactly the premise used in the figures I'd forgotten. Heh, I'm old, & yes, I inhaled...so cut me some slack.

The fans push more air than the restriction they represent, but there was a large gap between actual airflow in, compared to when it pulled instead. Don't listen to me, though; listen to OEMs. Primary cooling fans are characteristically pullers, by default. Show me a list of vehicles that use pushers instead. I've lots 'o 2ndaries as pushers, but never a primary.

Whatever. Besides, we all know he's several magnitudes higher on the evolutionary scale than the avg bloke here, so no worries, ey...his implementation will work. Consider it a given.
 
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the flexalite dual fans work fine. I use them and have run the piss outa my car and they have never givin me a problem. Getting a bigger radiator to fit would yeild better results than worrying about fan type.
 

· ma70-7m=1JZ
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Some fan blades are meant to push or pull. You should run the fan the way it was designed. I vote fur a puller too with the a/c fan wired to a manual switch.
 
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Bishop92T said:
I saw some old flow charts, I forget where. Once you get up to speed a fan in front of the radiator will only be a restriction no matter if it's on or not. A fan behind will be much less of a restriction. We're talking real world results here, not results from a laboratory. How about some proof from your argument? :)
Flow charts: every decent fan comes with one (funny, automotive aftermarket cooling fans almost NEVER include one, hmmm). However notice all the flow charts are for intake or exhaust configuration (push or pull). If there was a difference wouldn't we need two separate flow charts? Of course we would.

The flow charts are "real world conditions" test results, obtained by measuring a real fan. Most fans are measured like this:

Measurement of Fans Link


How about some proof from your argument?
I was going to type up a big breakdown of how this works, by braking down airflow into it's components, so the results would be obvious, but this is just silly.

Unfortunately this is a field that isn't covered very well on the internet, so I cannot link to a website titled "www.the_facts_of_radiator_ cooling_fans.com"

Let's just say, whatever flows INTO the radiator, must also flow OUT OF the radiator.

Correct?

If you restrict the exhaust of the radiator, then air cannot flow into it.

If you restrict the intake, more air cannot exhaust than went in, right?


______________________________


>>>>>>Quick and dirty example number one:

Think of air flow as bunch of ping-pong balls. 10 ping-pong balls go into the radiator, 10 have to come out, during a certain time period, let's say 1 second.

Now restrict the intake to the radiator, so only 5 ping-pong balls can get in (in one second), and only 5 will come out. We just halfed the airlfow volume!

Now move the restriction from the description above, to the exhaust side of the radiator. How many ping-pong balls will go through?

5 of course.



>>>>>>>>>Second quick and dirty example:

Let's say I told you that you have to breathe through a drinking straw for a 5 minute period.

I give you a choice however that, you can freely inhale or exhale without using the drinking straw.

What would you choose?

1) Inhale: no straw.....................Exhale: through the straw
2) Inhale: through the straw.......Exhale: without the drinking straw.

In which situation could you breathe more air?

Answer?....... It doesn't matter, they are the same. What goes in, must come out. Doesn't matter which is restricted.




________________________________________

Primary cooling fans are characteristically pullers, by default. Show me a list of vehicles that use pushers instead.
He he, the reason is very simple. There is almost never room IN FRONT of the radiator to install suitably large "pusher" fans. And any mechanical fan, driven by the engine has to be a puller, for obvious reasons.

The difference in performance is minimal, compared to the challenge of mounting the fans up front.
________________________________________


Cheers...........eggnog is kicking in, right about now :) ..Sdude.
 
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WTF? How you gonna fit a ping pong ball through a radiator? You are smoking KRACK!!! J/K shawn dude. GOOD explanation. Makes sense. You somehow always manage to pull a rabbit outa your ass. :)
 

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OK, I found this on the PermaCool site:

" In choosing an electric fan for primary cooling, four cylinder engines generally require 1,600 cubic feet per minute (CFM) minimum. Six cylinder engines generally require 2,000 CFM minimum, small cubic inch eight cylinder engines require 3,000 CFM and large cubic inch eight cylinder engines require a minimum of 4,500 CFM. Recommendations are based on stock engines and regular driving conditions. CFM estimates are based on the electric fan mounted behind the radiator in a "pulling" configuration. Electric fans mounted in front of the radiator, in a "pushing" configuration, are only 80% as effective."

I guess it boils down to what one chooses to believe.

And to all a good night.
;)
 

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I couldn't allow this to wait 'til morn.

"1) Inhale: no straw.....................Exhale: through the straw
2) Inhale: through the straw.......Exhale: without the drinking straw.

In which situation could you breathe more air?"

Some folks find it easier to blow, whiles others find it easier to suck. I guess it depends on which end of the straw you're on.
Ha! LOL.

I'm laughing w/you man, not at you; so don't get mad, ey ;)
 

· 25psi = 14" brakes :)
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The reason puller configured fans v/s pusher fans flow more is not about lab tests or anything so technical. Shrouds are the key. If you try and shroud the front of a radiator, you screw your cooling ability. Fans with shrouds are more effective. (Just look at a jet engine, enough said.)
The shroud effect is proven, and even a poor design adds air flow. In the case of a pusher, well, you are just adding restriction prior to the fan blades, then the fan moves the air, and some of it "leaks" and does not go through the radiator. With the puller, it is drawing air "through" the radiator, and in conjunction with the shroud, is very good at it. I often see overheating cars with missing shrouds. or guys who add electric fans with no shroud, and then they wonder why it does not work very well. Well, try and keep your stock shrouds, they fit the radiator, and if you can locate a fan in the opening of the stocker, the electric fan might give you excellent results. If you don't, you are loosing airflow that can be yours for free with the shroud.

Good luck on the fan issue. Sorry, but I could not help but post something into this fray.

Personally, I think the best option is the stock fan. Barring that, a high flow fan located with .5" clearance inside of the stock shroud will give you the best flow. (possibly better than stock, and you might pick up a few extra hp that the clutch fan is not using.)

Cheers:")
 
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Larry_A said:
OK, I found this on the PermaCool site:

" In choosing an electric fan for primary cooling, four cylinder engines generally require 1,600 cubic feet per minute (CFM) minimum. Six cylinder engines generally require 2,000 CFM minimum, small cubic inch eight cylinder engines require 3,000 CFM and large cubic inch eight cylinder engines require a minimum of 4,500 CFM. Recommendations are based on stock engines and regular driving conditions. CFM estimates are based on the electric fan mounted behind the radiator in a "pulling" configuration. Electric fans mounted in front of the radiator, in a "pushing" configuration, are only 80% as effective."

I guess it boils down to what one chooses to believe.

And to all a good night.
;)
Ah, good old Flex-a-lite. I'd like to see their theory behind this. And ask some of the engineers what they were thinking, when they made some of thier products (I'm sure it was the marketing department that screwed things up, they usually do :) )

Did I mention that those CFM figures are based on ZERO restriction on the fan? I guess if we had flow charts for their fans (which we don't), we would see how that 2000 CFM monster really only flows 500 CFM, when installed against a radiator.

Thanks Larry_A, for coming up with a possible source of this misinformation. Who knows, maybe something with their fans in particular (like inneficient blade design in one direction, when a fan is designed for pushing or pulling with a reversible fan blade), could be a reason for that statement.


I'm laughing w/you man, not at you; so don't get mad, ey
I know I can't change the world. But at least I can try to offer an alternative view, based on scientific principles.

I wish I knew half this stuff, prior to spending big money on basically garbage products. That's really what got me seriously into studying how things actually work, and why they work that way.

It really makes you appreciate OEM products, that 95% of the time are designed incredibly well, compared to what the shiny aftermarket products CLAIM to offer.

Cheers......Sdude.
 
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