Changing Fan On Gtr To Thermo Fans?

[STATUS]

No..just no

i concur dont do it.

Ive done back to back test on the dyno and the gain is so minimal you will never feel it and your lap times wont change an iota.

[Simon-S14]

nissan set up is so simple. may as well stick with what works rather then run wiring + fans+ relays etc

[zebra]

I had thermos on the gtst when I got it. Track days would always see water temps over 100

Put a stock clutch fan in with no shroud and temps never went above 85 after a 40 min session at Wakefield

Sucks the supra doesn't have room for a clutch fan due to the huge radiator it has now

[Bsa]

Rather the starting a new thread can anyone tell me what rb fan is the thinnest or are they all the same? Iv got a rb20 one on my 26 in the BMW I'm just worried it's to close has about 8mm clearance at the top How much can they flex

[Simon-S14]

the newer ones have less blade flex then older fans.

however just go and order an R31 RB30 fan hub. they are shorter then rb20/25/26

[Rekin]

i concur dont do it.

Ive done back to back test on the dyno and the gain is so minimal you will never feel it and your lap times wont change an iota.

+1

I ended up buying a 52mm radiator for my car but after installing it found out that the engine fan wouldnt fit... So ripped it out and put in some thermo's instead.

Next time ill make sure the radiator will fit, but to be fair i havent noticed any cons going down thermofan path as long as its done right. (however if i did the radiator right then i wouldnt have to get the thermofans right )

[Bsa]

Thanks simon now just need to find one

[zebra]

Try repco etc. they may have a Davis Craig one to suit.

[Bsa]

I'll have a look into that thank need to finish manifolds first

[sultanaz]

Anyone had a Greddy 51mm Radiator on a R32 gtr and fit the standard clutch fan and shroud?

Ive got that radiator which isnt installed yet and a clutch factory fan which has cracks all in it.... Either i go twin thermo fans or replace the factory fan IF IT FITS with this radiator.

Someone please help me if they got experience with this

Thanks !

Edited June 17, 2012 by sultanaz

[discopotato03]

The issues I see are that electric fans seldom pull enough air through the radiator and obviously a fan not running does SFA .

I believe there is a reason why Nissan stuck with the viscous hub belt driven fan and thats because they pull a lot of air through the core all the time .

I think many don't realise that for a cooling system to operate (read regulate) coolant temperature properly there needs to be a reserve of cooler water in the radiator , this is what allows the system to work as the power (heat load) increases .

For the radiator to reject a lot of heat it needs to have a LOT of airflow through it and many elec fans just dont have enough air pumping capacity to do the job .

True performance cars are different with cooling systems because they are intended to be worked hard for extended periods of time . Your average production road car is expected to be leaned on to get up to speed and then loaf along in consumption mode .

The big engined car like a Falcon doesn't generally work that hard and at low loads they don't have the same heat rejection requirements as a hard worked RB26 .

True race use cars should have a gale venting on their radiators because they in theory spend a lot of time well above 100/110 km/h .

I believe the effective compromise is to have a large mechanically driven fan with a shroud than allows it to draw air through most of the cores area .

RB is an S series is something the factory never had to find a fix for so you're on your own there .

A .

[Booki]

Kind of on topic.

My engine fan (assume you guys are talking about the big ass one in front of the motor, not the little thermo on the rad) has a few hairline crack's in it.

Where is the best place to get a replacement?

[kitto]

Kudos Motorsport have them in stock at a reasonable price.

http://www.kudosmotorsports.com/catalog/nissan-cooling-fan-genuine-nissan-skyline-r33-all-0196-r34-all-stagea-wc34-1296-p-1174.html

The RB25 fan with the odd looking blades is the most efficient. Even if you have an early type fan. If your replacing it, this is the one to go with.

There are two types though. Different bolt spacing between years. Check before you buy.

[Ryan1200]

The shroud is the key pull air through the entire core and a thermo wil work lots better maybe even the same as the stock fan lol.

[gotRICE?]

The shroud is the key pull air through the entire core and a thermo wil work lots better maybe even the same as the stock fan lol.

I dont think they will ever pull as much as the stock fan TBH.

I think where people go wrong is bolting them straight to the core. They need a good shroud setup, not just with two holes in it the size of the fans, and the fans need to be spaced off the core 30mm+ to give them a chance of pulling air through the whole core.

A friend of mine has twin thermos and a shroud on his Silvia (SR20) and it overheats after a while. Although interestingly enough its a bastard of a thing to get to operating temp lol. The shroud is so tiny that theres barely 15-20mm of space from the core to the shroud itself. Im guessing theres just not enough room for the air to move around.

Are 32 Engine bays a touch smaller?, as in the gap from the fan to the radiator support?. I think i mentioned earlier (or in another thread) that a 52mm Alloy job fit fine in my R33 with the stock fan and shroud. Only needed to trim off a 10mm piece at the bottom to slot past a bolt on (from memory) the power steering.

Edited June 18, 2012 by gotRICE?

[jjman]

A friend of mine has twin thermos and a shroud on his Silvia (SR20) and it overheats after a while. Although interestingly enough its a bastard of a thing to get to operating temp lol. The shroud is so tiny that theres barely 15-20mm of space from the core to the shroud itself. Im guessing theres just not enough room for the air to move around.

based on that its because his thermostat is stuffed. Which means that it doesnt open or close properly based resulting in those symptoms...

not to say it wont still overheat if his thermofan setup isnt adequate....

[gotRICE?]

As to above, this was tested with a brand new OEM thermostat, and also with the thermostat removed. Same result with all three tests. Think he might have it under control now mind you. Havnt seen/heard anything since i moved to Perth.

Edited July 12, 2012 by gotRICE?

[jjman]

maybe water pump or temp sensor then.

That is some strange behaviour...

Or it could be one or both of the above as well as an otherwise poorly performing thermofan setup that then leads to overheating at the other end of the scale...

Good luck

[Dajae]

I'm sure this has been mentioned else where, I just can't seem to think of it..

I'm on the "Stock fan works best" wagon, however I notice that the fan can visually appear to have a slight wobble. Is this just my eyes playing up, or is there a balancing issue? If so, how much more pronounced would this be at high RPM, in the case of an engine with the intended purpose of revving past 8.5K, etc. ?

[jjman]

I'm sure this has been mentioned else where, I just can't seem to think of it..

I'm on the "Stock fan works best" wagon, however I notice that the fan can visually appear to have a slight wobble. Is this just my eyes playing up, or is there a balancing issue? If so, how much more pronounced would this be at high RPM, in the case of an engine with the intended purpose of revving past 8.5K, etc. ?

yeah this is primary reason that i swapped to thermofans.

After a workshop 'trimmed' (butchered) the fan tips so that my new FMIC piping wouldnt hit on it it certainly seemed unbalanced (and obviosuly as some blades were trimmed more han others). And even if something doesnt look unbalanced, spinning at those speeds im pretty sure that any slight imbalance that isnt obvious to the human eve could still cause problems...

Done right im finding the thermofan setup better (52mm aluminium radiator + twin 12" thermofans on a thermoswitch relay in the coolant line).

In cold weather or doing over 60km/h (relatively vs the ambient temp and amount of stop start traffic im in) the fans dont need to be on. So saving alot of energy and the motor pulls so much more smoothly particularly from low rpm. Even with the fans on it seems to pull better than with the clutch fan.

Edited July 17, 2012 by jjman