Radiator Fan Placement

[Wynand]

Where is it best to mount the radiator fan; in front of the radiator (blowing through) or behind (sucking through). And why would you say so?

Take note that an air intercooler will also be fitted in front of the radiator. Will this effect the placement of fan or is it better to fit radiator in front of the intercooler?

[flyerncle]

Fans are available to fix to the face of it with plastic pins that go through the core fins and for my two pennies worth I would use one that sucks through as pushing air forward defeats the object of cooling.

[cornishmaid]

Originally Posted by flyerncle

Rads are available to fix to the face of it with plastic pins that go through the core fins and for my two pennies worth I would use one that sucks through as pushing air forward defeats the object of cooling.

Fair point but sometimes space is a premium factor on what type of fan to use?

[flyerncle]

Point taken, Pacet do a good range.

As posted previously the rad fitted to the race car being built is fitted inside the front chassis behind the rack and no fan is fitted as it will never sit in traffic,it was custom made and about £300 .

[tex]

put it behind the rad and make sure it sucks the air
if its in front it will cover off the area to wind cool by the area of the fan itself!

behind is best - (apparently )

[Wynand]

Originally Posted by tex

put it behind the rad and make sure it sucks the air
if its in front it will cover off the area to wind cool by the area of the fan itself!

behind is best - (apparently )

Make sense Tex when the fan is not powered whilst at speed, the wind will cause the fan to turn and in effect become a "disc" causing drag and slows down the air flowing through the radiator....

Any other suggestions?

BTW, the fan I have is one of those flat black universal plastic ones sold at most auto spares outlets.

[tex]

it will work fine as long as the fan is good and new and the radiator is good. You only really need super cooling with say turbo engines etc. Fan in front or behind will not make massive amounts of difference. But maximising something you can easily adapt is dont cover the radiator. You could add side panels to the radiator to stop air bleeding round the sides of it. Air moves to areas of least resistance. So going thro the fins isnt easy for it. Force it to go nowhere else but thro it.

[ThomasDK]

Are you not able to use the orig fan placed on the motor?

I am planing to use the orig. fan on my build. I am using a CVH 1,6L, Polo mk.3 rad. I have lots of space for the orig fan.

Is there any reason not to use the orig. fan other than space issue?

Regards
Thomas

[Wynand]

Originally Posted by ThomasDK

Are you not able to use the orig fan placed on the motor?

Is there any reason not to use the orig. fan other than space issue?

I do not have a donor car.
All bits and pieces on my build are bought separately - actually makes things easier in so much you are not stuck to one supplier so to speak, and you can mix and match. Much like a high end HiFi; result of the different branded components matched together are bigger than the sum of parts...

[davidimurray]

Originally Posted by tex

put it behind the rad and make sure it sucks the air
if its in front it will cover off the area to wind cool by the area of the fan itself!

behind is best - (apparently )

But if you have the fan tight behind the rad it will also block the airflow. Best option is to mount the fan a distance away from the rad - mine is about 3" behind the fan in a custom made cowl.