Thermo Fans

[Sarumatix]

I don't get it. Nissan ran termos on the maxima because they had to (engine in wrong way). They ran belt fan on the stagea because it was their choice - they could have put thermos on if they wanted to. Obviously some of you guys know more than Nissan's engineers.

Secondly - how are electric fans more reliable? They have wiring going in and electric motors (2 common causes of failure) and you won't get any warning if they fail. belt fan on the other hand the only point of failure is the belt itself, which costs about $5 to replace in regular maintenance.

are you trying to say that nissan engineers selected exactly the right balance of cost and performance for you tastes? have you modified anything on your car at all? if the answer is yes, you are being somewhat hipocritical?

The answer is that obviously a lot of things we do to our cars, are because we aren't using them exactly as nissan had intended (the stock product).

I have a large well known brand radiator, with a 16inch fan on my GTR. I haven't had water temp problems, although I took it very easy on the track. I would therefore not be 100% in recommending it to others. What I will mention however, is that as far as I can tell, when at speed the engine doesn't really need a fan. Unless you are 100% on throttle for relatively large stretches (track) or if you are stationary the great majority of your driving (traffic), of which I frequent neither .

Edited January 23, 2008 by Sarumatix

[chook]

When i tranform my Stag into a Neo, i remove the fan, because it take power, and then i put these on.

nice fans Jorn, they look great, i wasnt considering thermos until i saw these

http://www.flex-a-lite.com/auto/html/low-p...e-electric.html

[Stinky Rooster]

I don't get it. Nissan ran termos on the maxima because they had to (engine in wrong way). They ran belt fan on the stagea because it was their choice - they could have put thermos on if they wanted to. Obviously some of you guys know more than Nissan's engineers.

While I tend to agree with 99.9% of what you say in here Duncan, I have to disagree with this for a few reasons.

Firstly, the cooling system on a stagea was NEVER designed to operate in the Australian summer, particularly the West Australian summer. The Maxima, however......

Also, if tere was such little benefit in upgrading standard cooling systems, why do companies like Davies Craig and Aussie Desert Coolers thrive so well here? Because they are providing a much needed service. I think that if you ran an accurate temp probe across the radiator of any stock stagea in Aus you would get a rude surprise at how badly it handles the heat. Anyone that has experienced heat soak in their std SMIC will know what I mean.

[Duncan]

points taken gents - but the bottom line for me is my stagea is regularly put under very big loads (towing long distances) on hot days, aircon on etc, and the standard fan/raditor setup has never given me problems.

Which to me says the factory setup is fine, and those who are having trouble have a factory setup that is not working OK. That doesn't mean its worth the trouble to go thermos, just

replace your thermostat ($30-50)

replace your radiator (about $250 for a big alloy one)

Put good coolant in it and bleed it properly. ($20)

For about $300 you are back to a perfectly working system.

[pixel8r]

points taken gents - but the bottom line for me is my stagea is regularly put under very big loads (towing long distances) on hot days, aircon on etc, and the standard fan/raditor setup has never given me problems.

Which to me says the factory setup is fine, and those who are having trouble have a factory setup that is not working OK. That doesn't mean its worth the trouble to go thermos, just

replace your thermostat ($30-50)

replace your radiator (about $250 for a big alloy one)

Put good coolant in it and bleed it properly. ($20)

For about $300 you are back to a perfectly working system.

I'll add to this...

...if you're not happy with the extra noise the clutch fan makes, turn your stereo on/up.

I think that if you ran an accurate temp probe across the radiator of any stock stagea in Aus you would get a rude surprise at how badly it handles the heat. Anyone that has experienced heat soak in their std SMIC will know what I mean.

Probably true of the ratiator but I believe the std SMIC (s2 at least) will cope just fine until you start running more boost...

But yes the difference between your stagea's performance on a cold (<15deg) night and a boiling (>35deg) hot day is HUGE!

[Stagea_Neo]

Im just hoping to create less drag on the engine and maintain decent amount if not better airlfow.

[Dahtone Racing]

ford AU/EL fans are doing fine on my skyline

[GTR-32U]

While I will never dispute the power/fuel economy benefits of thermo fan versus Belt drive. I personally prefer thermo myself...However if a little extra power is the only reason behind it all then I really think you are wasting your money....The amount of time you will spend pulling it all out and custom installing it and the shear cost factor of it all...I reckon you could have made heaps more power for the same amount of cash elsewhere...My understanding of the clutch fans was ( Please correct me if I am wrong ) that the clutch releases power when up to operating temp and only engages when it exceeds...So in on the road driving provided your not in a 40 degree scorcher whilst the car is in typical motion it really shouldnt drain much if any power at all...thought about a cooler thermostat ? cheap little thing that may help your power

Edited January 24, 2008 by GTR-32U

[stagpower]

thanks for all the info people,but im still not sure which way im heading,but i gotta do it soon,my wagon sounds like a an ford 250x flow with the fan on its way out......i want to go with alloy rad so i thought twin thermos in a custom if need be shroud should be alrite,the new ones are meant to be good whilst using minimal power.....let you all know how i go

[petrolfix]

thanks for all the info people,but im still not sure which way im heading,but i gotta do it soon,my wagon sounds like a an ford 250x flow with the fan on its way out......i want to go with alloy rad so i thought twin thermos in a custom if need be shroud should be alrite,the new ones are meant to be good whilst using minimal power.....let you all know how i go

I have just installed a new aussie desert cooler street & strip radiator for $750 3 times the capacity of the old one and twin thermo's not shure on the cost of them yet i get my car back today from the auto electrictian. i ruined my fan and rad in an accident so i need new one's, any way and i wasn't settling for second best so i bought new.

A new radiator from nissan was $700 + new shroud $90 and i didn't even bother about asking how much a new clutch fan whould be.

I can gurantee thermo's will give you better fuel econemy and more power as it is one less thing that mechanicaly robs direct power from your crank. you now using electricity which your alternator is already providing ample and will continue to do so any way. my other argument is that i have a dirt driveway and at the moment and when you start the car with the clutch fan installed it first spins untill the fluid inside gets warm enough to let the clutch slip. this creates suction and sucks dirt up into the fan then spreads it through out the engine bay

[chook]

couple of questions, as Im thinking about my thermofan setup:

1. considering the RB25det Neo thermostat opens at 82 degrees---fully open at 95, so what thermofan switch should i consider ?

http://www.toymods.net/forums/showthread.php?t=5125

On at 90 Off at 85 ? on at 92 off at 87....or an adjustable one ?

2. Where is he best place to mount the thermofan switch ? radiator side of thermostat ?? has Nissan provided any blank threaded holes for one ? (I want to keep it factory looking )

[_Ryan_]

Dale- Where do you think the Japs test their cars? Australia. Alot of manufacturers test there cars in our backyard, due to space, and the lack of speed limits... Which is why capping the speed limit at 130 for NT was stupid, as it takes money out of the local economey.

Depending what is done to a car, i dont see why a professional clean(getting done shortly) and a new thermostat(45$ genuine) wont have it running sweet. Keep in mind newer cars run hotter to make them cleaner/more efficient.

Also when it comes to thermo's, dont touch davies craigs, I went though a book at Nissco, and there were fans that would flow heaps more than 2x 12"DC's, for less money, and they were thinner... i can check the brand if needed. That said, i have two brand new Davis Craigs in the shed.

[petrolfix]

couple of questions, as Im thinking about my thermofan setup:

1. considering the RB25det Neo thermostat opens at 82 degrees---fully open at 95, so what thermofan switch should i consider ?

http://www.toymods.net/forums/showthread.php?t=5125

On at 90 Off at 85 ? on at 92 off at 87....or an adjustable one ?

2. Where is he best place to mount the thermofan switch ? radiator side of thermostat ?? has Nissan provided any blank threaded holes for one ? (I want to keep it factory looking )

adjustible whould probly be the go but on at 90 and 0ff at 85 whould be safer for those hot summerdays.

[chook]

adjustible whould probly be the go but on at 90 and 0ff at 85 whould be safer for those hot summerdays.

thanks, ive decided to go for this product, programmable speed fan settings , varies depending on temperature. Also uses factory temperature sensor. Will marry it with a 16" Spal 2470CFM fan.

http://www.spalusa.com/fans/automated/acce...ies/fanpwm.html

Edited January 28, 2008 by chook

[silman]

If I could use a clutch fan I would. I've got an RB25DET in my 180sx, with 2 spal high flow fans. the thick ones not the thin crap ones like davies craigs. the problem is the spal fans draw 15 amps each, and the alternator can not cope with it. 80amps simply isn't enough. I had it rewound to 120, to find that the higher winding means the alternator does not charge until it has more revs. My rewound alternator lasted about 3 months. I have my fans wired up to a pivot fan controller and the fans are on 30 amp relays. Sure the fans flow a shitload of air but now i've got electrical problems. it doesn't help that i've got a boot mounted battery, even if it is an optima yellow top d34.

At the moment I'm going to buy a new alternator as the one i originally began with was a stock one from a s1 rb25det. put simply it had had it's day at over 10 years old. I'm going to remove one of the 12" spal fans and install a repco 12" fan rated at 8 amps (basically, your run of the mill cheap china medium sized fan). Hopefully 22 amps drawn at once, instead of 30 amps is not going to be too much for the alternator to cope with.

When I took the alternator back to the sparky he said it was a diode, seperate to the regulator. I'd recommend installing extra grounds for the alternator too.

Edited February 5, 2008 by silman

[chook]

good advice,

the 16" spal im installing ( http://www.spalusa.com/fans/automated/tech_sheets/2082.pdf ) pulls 22 amps @ full speed. With the automatic variable speed controller Im hoping it will only use full power sparingly. Am I right in assuming @ half speed for example the current draw will be significantly less than 22amps ?

[silman]

Put it this way, my alternator is stuffed and the power fc is showing as low as 11.6 volts ad idle. at first startup the car is at 13.6 volts, after driving for a while, and the water temp hits 75 degrees, my pivot fan controller turns on the fans. by that time, the alternator has reached normal operating temperature, and is at 12.8volts max when it should be at 14v. When the fans turn on it is going down to 12.2 which is pretty horrendous. It has always been this way from the first day I installed the spal fans. They're definitely heavy duty fans, not your average run of the mill items. I would love to use them as a pull setup, but there's no space even for a slimline, with my 53mm koyo radiator.

The variable speed controller should limit the drawage at half speed, but when you turn it up (i'd advise slowly) if your alternator is more than say 7/8 years old and is the stock 80amp rated one, then you could run into the same problems I have had.

I'd be interested in hearing what the alternative alternator was that was used by somone who i think suggested it in this post. I've been to Ashdown's here in Brisbane, and they say that 80amps is the highest rated alternator for the RB series engines, but there was a 90 amp item from a cedric? which apparently used an rb25DE (no turbo). The only option to definitely fix the problem would be to get a holden/ford item at 130+amps, but the alternator belt depth and length would be way out. Any input for those that have used alternators from a different car much appreciated.

I'll see how a new replaement alternator goes next week, and if it the voltage still drops plenty, then I'll install the new spare repco one I have as a comparison, and sell the spal on here for someone to copy my setup.

Edited February 21, 2008 by silman

[chook]

I was looking at the SPAL dual 12s, http://www.spalusa.com/fans/automated/tech...ts/30102130.pdf , but at around 40 to 50 amps !!!! that was ridiculous, and i also have the problem of the thicker KOYO radiator. But the 16" should slide in fine, on paper anway.

Ill have to keep an eye on things like you suggest.

[chook]

Here's a 110amp upgrade, not sure of the availablity here , http://forums.nicoclub.com/zerothread/260788

Also some Z32s use a 90amp and non-turbo R33s possibly use 90amp

[silman]

LOL that is a lot!... these are the ones i have - the table in the lower left corner says at least 15amps per fan, not sure what the static pressure stuff is about but it says 1630cfm each;

http://www.spalusa.com/fans/automated/tech...s/2038-2025.pdf

here's a pic;

http://img213.imageshack.us/img213/3009/1787815en3.jpg