Just wanna know if the dual 15" flex a lite electric fans really improve horsepower or just only really help for cooling? Need some advice from some senior members or somebody that installed one in their truck.

2001 F150 4.6
hypertech power programmer
K&N Gen II kit
BBK TB with Airaid Spacer
flowmaster 40 series dual exhaust
24" katana azzad rims

 

YES they are worth it!!!(my opinion) I have the Flexalite FAL-270 fans on my 4.6L Expedition and I love em! The stock fan weighs right at 10 lbs.! I could tell a NOTICEABLE increase in power, especially starting from idle, because you don't have 10lbs. on the end of the water pump weighing down the rotating mass. If I can tell a difference in my big Expedition, you should really be able to in a F150! Get em and let us know what you think!

 

HotRod22,

By chance did the flex a lite fans cause more strain on the alternator or battery and did you have to upgrade to a heavy duty alternator and deep cycle battery?


2001 F150 4.6
hypertech power programmer
K&N Gen II kit
BBK TB with Airaid Spacer
flowmaster 40 series dual exhaust
24" katana azzad rims
Harley Davidson Valance
Go Rhino Speed Tubes
Grillcraft Speed Grill

 

I put the duals on my truck, 99 F150 w/ 4.6 and although it cools alot better I didnt really recognize a gain in HP and lost 2 MPG's. Not completely sure if it was worth the money.

 

How could an electric fan make you LOSE 2 MPG?

 

The engine doesn't have to turn the manual fan; it's as simple as that. More horsepower and increased mileage from reducing parasitic drag.

 

red wing, I think the setting on the module is set too low therefore, not allowing the motor to get to operating temp. I think that is why I lost 2 MPG. I have a infrared temp gun I am gonna try on it this weekend to see what temp it comes on at exactly. Does anyone else have any ideas how to check that may be more accurate?

 

Stock alternator, stock battery, no problems! I think I even gained a mile or two.

 

Turn the adjusting screw so that the temp would have to be sky-high to activate the fans.

Now, drive in an area free from traffic lights (and traffic, if you can) for at least 5 miles or so. Allow the truck to warm up completely, trying to stay above 35 MPH or so. This will allow the engine and cooling system to get up to a "normal" operating temperature.

Once you are at "normal", pull over very quickly, pop the hood and adjust the controller so that the fans click on. Then, drive a few miles more (again, at 35 MPH or faster) so the truck can cool down a bit and then stop very quickly again. The fans should not be running yet, but should kick on shortly after you stop flowing air across the radiator.

I adjusted mine out in the country, where I could drive 50 - 60 MPH and let everything stabilize, then pulled over quickly and made my changes.

After I was finished, the fans never ran if the truck was moving over 30 MPH or so and the temp gauge (a "real" Autometer, not the factory unit) was so stable it was virtually useless.

Hope this helps...

 

thanks bman

 

I've got a question.

Wouldn't the engine get up to operating temperature even if the fans were cooling the radiator 'too much'?

Once the coolant in the engine gets to a set temperature, the thermostat will open and allow coolant from the engine to flow into the radiator and vice-versa. Once the colder coolant from the radiator reaches the thermostat it will close again. Now granted the engine temperature will drop a little say five or ten degrees but is that enough to affect engine efficiency?