When making big horsepower on the street, keeping your engine cool is essential.
Sitting in heavy traffic with a high horsepower engine, a mechanical fan just won't cut it.
Mechanical fans rely on engine RPM and when sitting at idle, they just don't spin fast
enough to keep your engine cool.
Mechanical fans also rob your engine of horsepower and fuel economy since they are driven off
the crankshaft.
They simply can't compete with electrical fans when it comes to efficiency.
A radiator only works if there is airflow through the radiator core.
An electrical fan provides constant airflow even when the engine is idling when your engine
needs it the most.
And since they are electric, they do not affect engine horsepower or fuel economy.
When choosing an electric fan, here are a few factors you should be aware of.
Electrical fans can either push air through the radiator or pull air through it.
A pusher fan sits in front of the radiator.
When a vehicle is moving, a pusher fan can obstruct airflow due to it's positioning in
front of the radiator.
A puller fan, on the other hand, sits right behind the radiator, it pulls through and
has less impact on airflow at high speeds than a pusher fan since it sits behind the
radiator.
Puller fans provide more cooling capacity than pusher fans.
The determining factor on whether to use a puller fan or a pusher fan is the amount of
room that you have.
Always choose a puller fan, but if space is an issue then use a pusher fan.
When it comes to diameter, you should get a fan that covers as much of the radiator
core as possible.
Measure the area with an existing fan and shroud removed to find out how much room you
have to work with.
larger fans will keep your car idling in the heat for a lot longer period of time without
overheating.
Always allow some clearance between the fan motor and the engine.
You do not want these parts touching each other.
Most of the time a single fan is all you need, but if you have added a much larger engine
or are making big horsepower, then you may want dual fans to maximize the amount of airflow.
If you're not having a problem with overheating, then a single fan will suffice, but if you
have made big, significant upgrades, such as a turbo or a supercharger, then dual fans
will help provide the additional airflow needed.
Straight and curved fan blades come down to a difference in noise vs airflow.
Straight blades move more air but are more noisy.
On the other hand, curved blades are quieter but don't move as much air so it all depends
on your application.
If you desire a more quiet fan, then the curved blade is the way to go, but if you need all
the airflow possible, then go for the straight blades.
To get maximum airflow through the radiator core, you should use a fan shroud.
A fan shroud ensures the air is moving through the radiator core and not around it.
A radiator is useless without airflow, a fan shroud helps direct air flow through the core.
Whether it be plastic or aluminum, make sure you use one in your vehicle.
Manufacturers rate fans by CFM, CFM stands for cubic feet per minute so an electrical
fan with 1500 CFM rating will push 1500 cubic feet of air per minute.
Follow this general guideline for engines.
As a basic rule of thumb, the more power your engine makes, the higher the airflow you want.
If you are using a turbocharger, supercharger, or have a large engine, then you will want
the maximum CFM fan available.
When a max airflow fan does not provide enough cooling for you and you have taken into account
all factors mentioned here, then you might consider looking into a larger radiator.
Another factor to look at is the current draw.
The more current the fan draws, the more airflow it will have.
A more powerful electrical fan can draw air through multirow, radiator, and air conditioning
cores.
Be sure to use a relay kit when wiring an electric fans.
We have relay kits designed to intergrate with OEM wiring.
Choose a relay kit with or without a stainless steel electronic sending unit.
Sending units offer hands free control of your electric fans, simply choose a sender
with an on/off temperature that best fits your needs.
By taking into account these simple points, choosing the right electric fan for your vehicle
will be straight forward and keep your engine happy for years to come.
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