Electric Fan

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Fred D.
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I was thinking about gaining some horse power, and know that a electric fan helps with parasitic friction power loss. Has any one here converted their Q to a electric fan instead of the belt driven one. I know many people hear would not want to do a conversion like this, because it could void a warranty. I was thinking a 16 inch 2-3000 rpm fan, Im shure this would be plenty of air flow to cool the radiator. I would have to get a smaller belt to refit without stock cluth fan, please let me know if this sounds like a good idea.


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elwesso
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The problem is that it puts a big extra strain on the alternator... It wont really gain anything, IMO.

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Jeff Williams
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The few HP you gain are at a very expensive price. It is a good idea that I have contemplated many times. If I ever get my car back to new OEM standards, I might start doing some of these type of mods. Put 2 batterys in the trunk, and disconnect the A/C, alternator, fan, & PS pump. Do a couple dyno runs, to see what the real HP increase is. Probably get more gain out of a higher stall torque converter.

Fred D.
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I would expect around a 15 horse power gain, based on research. The price should be around 150$ for a really good qaulity electric fan. With Infinitys its all ways expensive to gain horse power, but did I mention switching to a electric fan also saves gas. From 1-3mpg because the engine doesnt have to pull the clutch fan. Their are many diffrent electric fans some use a lot of amps like 18 amps, but their are many that only use 9 amps. I dont think the cost or the power consumption is a negative, considering the gains.

TgduMg
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Fred D. wrote:Has any one here converted their Q to a electric fan instead of the belt driven one.
An owner of one the quicker Q's on this forum Sijoko did this mod to his 94 Q45 and a few FX45 owners were looking at doing e-Fan mods as well.

A gentleman who has done some early G35 conversions states that it is good for a gain of 8 to 10 RWHP on the VQ35. No it's not a big gain by itself but 8 here, 13 there, etc... does add up.

Danisiti 1

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Ezekial
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i use a davies craig 16" electric fan

cant comment on gains though. i have never used the standard engine fan

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Flagship-Q
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I removed my mechanical fan 2 weekends ago. I noticed that the motor will windup faster (less things to spin I guess) and I did gain 1-2 mpg also. I'm getting a 2 speed electric fan fron a early to mid 90's Ford Taurus 3.8l (from car-part.com for about $30) that has more than enough cooling power for the Q. Many jeepers that do a V8 conversion recommend this stout fan. I'll let ya know!

DrewQ45
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Flagship-Q wrote:I removed my mechanical fan 2 weekends ago. I noticed that the motor will windup faster (less things to spin I guess) and I did gain 1-2 mpg also. I'm getting a 2 speed electric fan fron a early to mid 90's Ford Taurus 3.8l (from car-part.com for about $30) that has more than enough cooling power for the Q. Many jeepers that do a V8 conversion recommend this stout fan. I'll let ya know!
Here's a writeup showing how to accomplish this conversion with the very same fan on a Mustang.

http://www.fordmuscle.com/arch...x.php

However....

"The stock 75amp alternator will not be able to handle the added load of the new fan, especially after we saw how much air it can pull. You can check out the 3G alternator upgrade here.

Using a Fluke digital clamp ammeter, we tested the starting (or inrush) current draw and the operating current draw. The Taurus fan pulled a little over 130 amps on startup (only for milliseconds) and settled down to right around 40 amps using the high-speed wire. This is why you must upgrade to the bigger alternator and a Bosch high-powered relay"
Modified by DrewQ45 at 6:41 AM 3/29/2007

Q45tech
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http://emp-corp.com/media/SAEP...7.pdf

Fan pump power is proportional to the cube of speedhttp://emp-corp.com/media/SAEP...0.pdf

More:http://emp-corp.com/techLibrary/

DrewQ45
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The Taurus fan draws 40 amps and produces 2000 cfm. Here's an aftermarket moving the same volume of air that draws only 11.3 amps. The Taurus' motor seems inefficient, but hey, it was designed for use with a Taurus.

http://www.jcwhitney.com/autop...04118

Q45tech
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Maximum flow UP TO 2000CFM unfortunately that means in free air not drawing thru a condenser or radiator with back pressure of engine bay.

Always a good idea to have 2 electric fans to limp home on one when one fails.

Just buy additional alternator insurance!................as oem 110 amp is already stressed.

DrewQ45
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Q45tech wrote:Maximum flow UP TO 2000CFM unfortunately that means in free air not drawing thru a condenser or radiator with back pressure of engine bay.

Always a good idea to have 2 electric fans to limp home on one when one fails.

Just buy additional alternator insurance!................as oem 110 amp is already stressed.
All true. I'd much rather have two fans than one. Wonder if there are any hi capacity alternators out there for a Q? If alternator has to be upgraded, which it does, then the logical time for this mod would be right after alternator failure.

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pdqwrx
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I just installed a pair of Flex-A Lite's in my S13 (240SX) and love them. They don't make a ton of noise and blow a crap load of air (Highly technical term). They keep up with my 350 Hp or so SR20 with NO problem and don't seem to be a big burden on the charging system even with my tiny little race battery. I can also attest to some OEM fans pulling a ton of juice. I have a 03 GTI 1.8T and when the electric fans come on it will pull my charging voltage down to 12.5 volts from a healthy 14.5 volts. I will probably replace it's fans very soon to save the alternator and allow for my stereo to be played when in stop and go traffic with the AC on. But anyway, the 220 "Puller" fan is what I used in the S13 and it rocks.

Good LuckScott

Q45denver
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Are the mechanical belt driven fan more reliable?

Anyone know if the condenser fan on a 1995 comes on independent of the A/C, i.e, thermostatically controlled?

My 1995 seems to take a long time to warm up and either there is something wrong with the condensor fan coming on when cold (I've noticed this several times) or I need to switch to an electric engine fan to better control cooling?

I was thinking a Spal 16 inch puller fan with a variable speed controller would fit well within the existing shroud. Would 2400 cfm be enough for this application?

Would the dealer be able to diagnose a condenser fan problem with a Nissan Consult?

DrewQ45
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Q45denver wrote:My 1995 seems to take a long time to warm up and either there is something wrong with the condensor fan coming on when cold (I've noticed this several times) or I need to switch to an electric engine fan to better control cooling
The mechanical fan is of course more reliable... less that can go wrong with it. Your warming/cooling issue may be caused by the thermostat staying open. When's the last time you had it changed?

Q45tech
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Start and stop temps and speed vs temp [94 tri speed fan] are all fully outlined in your FSM............controlled by ecu from coolant temp sensor and Ac cpu.

To me thermostat should be replaced every 3 years, 4 at max. But then I like things to behave as brand new.

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Skibane
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DrewQ45 wrote:Your warming/cooling issue may be caused by the thermostat staying open.
Yep, there's a real strong possibility that the thermostat is your problem. Normally, the Q warms up amazingly fast (120 seconds in summertime, perhaps double that during the winter). I've never driven another vehicle that came up to operating temperature as quick.

And, more good news: Installing a new thermostat is a cheap fix.
Modified by Skibane at 8:36 PM 4/8/2007

Q45denver
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Good point on the thermostat, I think I have a new one for my 1990 that should fit.

In addition to increase in mileage and horsepower a secondary benefit for an electric fan might be longer engine and injector life since the fan runs after the engine is shut off.

Spal uses a long life motor. A dual fan system should be at least as reliable as the OEM fan? Looks like this dual 11 inch fan might fit and has a higher CFM than the 16 inch (also on sale). I'ill have to get rid of the existing shroud however.

http://www.a1electric.com/Merc...02052

Maybe this will also allow me to remove my oil filter from the top since there will be alot more clearance behind the radiator.

Q45denver
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Any reason why the condensor fan would be on with a stone cold engine and A/C off?

qship96
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defective temp sensor? defective tripple pressure switch?

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Skibane
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Q45denver wrote:a secondary benefit for an electric fan might be longer engine and injector life since the fan runs after the engine is shut off.
...which is more than offset by the shorter battery and alternator life...

Quote »Spal uses a long life motor. A dual fan system should be at least as reliable as the OEM fan?[/quote]BOTH fans will fail if the relay gets moisture or dirt inside it, or the thermostat contacts open up, or the fuse holder gets corroded, or the wiring insulation gets chaffed and shorts out, or...

As DrewQ45 mentioned, the belt-driven fan is inherently more reliable. Sometimes, the simplest solution is the best one.

Q45tech
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I'm not sure that removing mechanical fan would have any effect on EPA style mpg since no test has very much rapid acceleration.

Measuring the coolant temperature and the resilence to maintain 174F will only be known in a July August Traffic jam.

Luckily it will be easy to rip out and trash electric fans that don't do the job=======keep the old fan in the trunk and some tools.

DrewQ45
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Q45denver wrote:I was thinking a Spal 16 inch puller fan with a variable speed controller would fit well within the existing shroud. Would 2400 cfm be enough for this application?
The existing shroud would probably envelope the fan unless you were thinking of actually mounting the fan on the shroud? (disaster) Each fan should come with a shroud of it's own allowing it a good seal against the radiator. I would think that getting rid of the existing shroud would be desirable since it extends well into the engine bay taking up valuable space and making things much harder to work on.

IMHO, switching to electric only makes sense if there are upgraded alternators available for the Q, something I have not seen. There are a few things on this car that have barely, if any room for expansion... namely the charging and cooling systems. (probably why it warms so fast)

Q45denver
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Skibane wrote:
...which is more than offset by the shorter battery and alternator life...

BOTH fans will fail if the relay gets moisture or dirt inside it, or the thermostat contacts open up, or the fuse holder gets corroded, or the wiring insulation gets chaffed and shorts out, or...

As DrewQ45 mentioned, the belt-driven fan is inherently more reliable. Sometimes, the simplest solution is the best one.
Increased reliablity of alternator and batttery offsets increased relaibility of engine, injectors, waterpump, hoses, etc?

If you have that much problem with mositure and dirt your engine probably won't run anyway.

A mechanical fan with a clutch is more simple than an electric motor with a thermostat?

Q45denver
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DrewQ45 wrote:
The existing shroud would probably envelope the fan unless you were thinking of actually mounting the fan on the shroud? (disaster) Each fan should come with a shroud of it's own allowing it a good seal against the radiator. I would think that getting rid of the existing shroud would be desirable since it extends well into the engine bay taking up valuable space and making things much harder to work on.

IMHO, switching to electric only makes sense if there are upgraded alternators available for the Q, something I have not seen. There are a few things on this car that have barely, if any room for expansion... namely the charging and cooling systems. (probably why it warms so fast)
Fan comes with solid mounting brackets. Not recommended to mount to core except for short periods of time. The mechanical fan is more in the way than the existing shroud. The dual fans usually come with a shroud but the singles are designed to work with the existing shroud. I've had several Hondas that had tiny alternators and batteries with electric fans that seemed to work just fine. These cars with electric fans seem to warm up much faster.

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elwesso
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IMO itd make more sense to put some clever vents on the hood instead of having a fan... Then you could just run a turbo timer for a minute or so and the air woudl go out of the car...

Besides, its always better to let the motor idle for a minute or 2 before a hot shutdown...

Q45denver
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Q45tech wrote:I'm not sure that removing mechanical fan would have any effect on EPA style mpg since no test has very much rapid acceleration.

Measuring the coolant temperature and the resilence to maintain 174F will only be known in a July August Traffic jam.

Luckily it will be easy to rip out and trash electric fans that don't do the job=======keep the old fan in the trunk and some tools.
These guys claim up to 15% improvement in mileage.

http://www.electricfanengineering.com/electric.htm

Wouldn't an electric fan work better in a traffic jam since a mechanical one is limited to the speed of ithe dling engine?


DrewQ45
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Q45denver wrote:Increased reliablity of alternator and batttery offsets increased relaibility of engine, injectors, waterpump, hoses, etc?


It's all relative. Take my Q... @ 211K on original engine + injectors, I doubt if an eletrical fan would improve longevity much/any on OEM design. Alternator failure, however, would arrive in a speedier fashion.
Q45denver wrote: A mechanical fan with a clutch is more simple than an electric motor with a thermostat?
Very much so. Simpler by design. All the fan failures I've seen have been due to plastic disentegration of the blades. The fan clutch is very reliable and will outlast any electric motor (brush wear) 3+ times over.

Q45denver
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Q45tech wrote:Start and stop temps and speed vs temp [94 tri speed fan] are all fully outlined in your FSM............controlled by ecu from coolant temp sensor and Ac cpu.

To me thermostat should be replaced every 3 years, 4 at max. But then I like things to behave as brand new.
Still not sure if the condensor fans run independent of the A/C being on.

Q45denver
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DrewQ45 wrote:

It's all relative. Take my Q... @ 211K on original engine + injectors, I doubt if an eletrical fan would improve longevity much/any on OEM design. Alternator failure, however, would arrive in a speedier fashion.

Very much so. Simpler by design. All the fan failures I've seen have been due to plastic disentegration of the blades. The fan clutch is very reliable and will outlast any electric motor (brush wear) 3+ times over.
Yes, your lucky, but I've had four engines and several set of injectors in my 1990. Never had an alternator fail however. I think some of the new electirc fans are rated for 50,000 hours with nylon reinforced blades.


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