SPAL electric fans can either replace your current engine cooling fan or be custom mounted to oil coolers or intercoolers. They are triggered electronically through a thermostat that is pre-set from the manufacturer for your OEM cooling fan. If you are using SPAL fans for a custom application, then they have relays and harnesses to trigger the electric cooling fans.
Choosing the right radiator cooling fan is based on radiator core size, space required for the cooling fan, radiator material and number of cores and if a shroud is utilized or not. Radiator core size determines the diameter of the automotive cooling fan that you will need. Too small of a fan and parts of the radiator will not be cooled. On the other hand, if the engine cooling fans are too big, they will hit the shroud and not rotate, unless you are creating a custom fan shroud. At that point, you have total control over the size.
The space that is available for the cooling fan must also be taken into consideration because if you need a small fan, you would not want to buy a large profile cooling fan. SPAL cooling fans are available in small profile electric fans and medium profile fans to fit small areas in between the radiator and engine. SPAL cooling fans are also great for oil coolers and can be mounted however you would like. You can then use SPAL accessories to allow your fans to turn on when the temperature reaches a certain degree.