By now you should all know the benefits of replacing the stock belt-driven fan with an electric unit, but if not, here is a little refresher. The first benefit will be for all you power junkies out there, which is freeing up some horsepower—anywhere from 5-10 hp (sometimes more) than with a clutch fan. Since the fan will no longer be driven from the motor, all the power it took to turn said fan is free to move to where it counts: the rear tires.
The second benefit will be better cooling capabilities at lower speeds. Why, you ask? Well when you are sitting in traffic or at a light, it's up to the fan to pull air through the radiator, and since an electric fan is not dictated by engine rpm it has the ability to spin faster and pull more air than a belt fan spinning at idle.
One thing that has most enthusiasts a little gun shy when it comes to electric fans is the thought “I've heard the electric stuff fails, and I would rather stick with my tried and true mechanical fan.” That may have been the case back in the infancy of aftermarket electric fans, but thanks to better fans and smart controllers, the fans can last much longer and provide years of trouble-free service.
Our '70 Z28 has a big clutch fan hanging off the front of the motor and a huge plastic shroud that visually covers most of the front of the engine. We wanted to add a modern electric fan and controller setup and ditch the ugly stuff while staying within a budget of right around 400 bucks. One thing to note is we have already installed a high-output alternator to handle the added power consumption of the fan. The install is in this very issue, so make sure to check it out.
For the fan, we looked to CFR Performance and the company's big 16-inch high-performance universal electric fan that flows 2,300 cfm @ 2,479 rpm. The unit features eight fully balanced curved blades driven by a reversible, sealed bearing, high-torque motor, and a durable plastic mounting ring. To make installation a snap, CFR also offers universal shrouds that are pre-drilled for the CFR Performance electric fans. No more push-through clips or ugly looking metal straps holding the fan. Plus, adding a shroud to the radiator allows for 100-percent cooling of the radiator core instead of the area directly in front of the fan.
To control the fan, we took a trip to Summit Racing and ordered an F5 single fan controller from Painless Performance. The F5 fan control system includes an underhood-rated, solid-state pulse-width modulation controller, 3/8 NPT threaded temperature sensor, large-gauge fan wires and a labeled vehicle integration wire harness, mounting hardware, 70-amp fuse, and connectors. This is one sophisticated piece that takes the mundane task of turning the fan on at the correct temperature to the next level.
The F5 will turn on the fan at a user-set temperature at 50 percent, and if the temperature continues to increase the controller speeds up the fans little by little until it reaches 100 percent. This not only increases the life of the fan but also will keep the engine temp more consistent instead of it going it up and down as the fan turns on and off. The controller also has parameters to turn the fans on to 100 percent when the A/C is engaged, turn the fan off at highway speeds (if your car is equipped with an electronic speedo with a VSS signal), and there is even a manual override toggle switch that allows you to turn the fans on or off for those times when you are working on the car.