My upgraded fans arrived today with nice present

[V8Dom]

thanks guys, i wasnt expecting that.

Amazing how just a small presents bring a smile to your face especially if you are having a crap day



thankyou

[845ste]

[UltimaCH]

Nice gift indeed for those who still write on paper...

Would like to know what upgraded fans you got from the factory

[BobE]

Have you gone for the Evo versions in front of the radiator? Do you need the extra cooling power?

[V8Dom]

yes they fit the EVO too but mines a GTR

ive upgraded as i have seen temp raise recently with power mods and these upgraded fans are far more efficient

Charles Dunn has fitted a few on sbc cars and seen huge drops in temps when turned on.

[Ultimike]

I've got the evo fans with the evo grill set and it's the best mod I have made to the car. No longer fear traffic on the motorway and it's much more useable every day and for its sporting bears work.

[BobE]

Ultimike said:

I've got the evo fans with the evo grill set and it's the best mod I have made to the car. No longer fear traffic on the motorway and it's much more useable every day and for its sporting bears work.

How involved is the change? From what I can see the new fans are suspended through the radiator and I presume you then need a new uprated power feed via relay(s). Is the grill set just the air outlet as I can't believe there is much obstruction from the GTR inlet mesh.

[F.C.]

Are the fans shrouded?

[GtrMan]

What is the CFM of the new fans compared to the old type.?

[BobE]

Here is my take - only the factory can provide the exact detail. From surfing the interweb I think the fans fitted to my GTR which is a 2003 registered car have a cfm of about 680 and draw about 5 amps each. There are much more powerful fans available even in a 10" impeller diameter but most have a depth too great to go on the downstream side of the radiator. Hence the EVO has fans on the other side of the rad and without a shroud. I'm guessing from is available that they are around 2000cfm but probably draw 10 to 15 amps. So the cooling will be dramatically improved probably even with the restrictive outlet mesh as most of the resistance is going to be in the radiator matrix anyway. There is only a single 25amp fused relay controlling the pre- EVO fans which won't handle the new fans current so I guess a pair of such relays are now required. I think there is 2000cfm fan available in the USA which could fit in the current downstream position but it will still need a further relay etc.

[GtrMan]

After doing some research on the new Evo rad fans I found some pictures on an Evo build site that shows the new fans.

These are the Comex F13P-12E8102-13B , these are 255mm ( 10inch) fans, their cfm is rated at 990 cfm but they could be more efficient since they are blowing not suction type.

http://shop.comex-europe.com/cgibin/prodotti_alleg...

I am not sure if lately these fans were up rated to a larger size.

Edited by GtrMan on Sunday 26th February 18:00

[BobE]

GtrMan said:

After doing some research on the new Evo rad fans I found some pictures on an Evo build site that shows the new fans.

These are the Comex F13P-12E8102-13B , these are 255mm ( 10inch) fans, their cfm is rated at 990 cfm but they could be more efficient since they are blowing not suction type.

http://shop.comex-europe.com/cgibin/prodotti_alleg...

I am not sure if lately these fans were up rated to a larger size.


Those fans are thin enough to fit downstream so it seems odd they are fitted to the other side of the radiator as they have a higher output when sucking, but maybe there are other packaging reasons for them to be fitted the way they are in the Ultima installation - or as you say they maybe larger than 10". Compared to what I think was fitted originally they are significantly more powerful. My previous car was a 4 litre TVR Tuscan and that had a pair of 12" fans with an output of around 1600 cfm each and they came on sequentially depending upon coolant temperatures so it gives an idea of what is needed. I found these on line :
http://www.mishimoto.co.uk/race-line-high-flow-fan...
They have a much higher output but the standard versions but are suck not blow and are too deep to fit in the 'suck' mode but maybe the company will do a blow version for fitting on the upstream side of the radiator.
Whatever some electrical feed uprating is required.

Edited by GtrMan on Sunday 26th February 18:00

[V8Dom]

cant you just wire up wrong way to reverse the thrust?

[BobE]

V8Dom said:

cant you just wire up wrong way to reverse the thrust?

There are three issues here. Firstly most but not all dc motors can have their direction of rotation reversed by changing the wiring polarity. Some - and I think the Mishimoto race fan motors may be such an example - cannot as they use a stator winding rather than a permanent magnet. Motors of that type will only run in one direction no matter what you do with the polarity. Secondly fans aren't that efficient if you run them backwards. It's like a propellor or wing going in reverse. So their output would be much less. Finally it depends on what thrust bearing arrangements there are - the impeller or fan is creating a force down the motor shaft equal to the 'lift' created by the fan. If the unit is only designed to run way it won't like being driven in reverse. However fans like the Tripac ones are designed to run in either direction with the fan element taken off and reversed to change the thrust from suck to blow etc.
Can you tell us the fan diameter of your new parts and their cfm - are they Comex/Revotec parts noted above?

[F.C.]

The issue here is surely the fact that the fans only cover part of the radiator a simple shroud arrangement would allow the fans to pull/push air through the whole core area.

[BobE]

F.C. said:

The issue here is surely the fact that the fans only cover part of the radiator a simple shroud arrangement would allow the fans to pull/push air through the whole core area.

That's true as you use more of the radiator surface area but there is very little room to do that - on my car there is less than 10mm between the centre boss on the cooling fan and the air outlet mesh. That would mean a very shallow shroud above the radiator matrix. If you do that then there is a real risk of reducing the cooling at high speed. It's down to the space available - but the real problem is the use of 10" fans - the larger the fan diameter the larger the airflow rate. The other issue is the cfm value is without any obstruction to the airflow - put a very thick radiator matrix in the air pathway and you won't get anywhere near the airflow rate quoted by the fan manufacturer.

[F.C.]

BobE said:

That's true as you use more of the radiator surface area but there is very little room to do that - on my car there is less than 10mm between the centre boss on the cooling fan and the air outlet mesh. That would mean a very shallow shroud above the radiator matrix. If you do that then there is a real risk of reducing the cooling at high speed. It's down to the space available - but the real problem is the use of 10" fans - the larger the fan diameter the larger the airflow rate. The other issue is the cfm value is without any obstruction to the airflow - put a very thick radiator matrix in the air pathway and you won't get anywhere near the airflow rate quoted by the fan manufacturer.

Agreed the pressure drop will be high, I believe though that one of our American friends runs a shroud successfully, the cooling issues talked about are normally traffic stop start type.
I'm fairly sure the use of a cowl at high speed will not affect the performance cooling wise, after all the air is entering the full core and then channelled through the fans and shroud.