Can anyone rebut or confirm what I read recently about electric fans that are big enough to provide adequate cooling are a huge amp drain and that the additional draw creates more work for the engine which offsets the gains from switching out the EO fan? I agree it would be a draw, but is it a problem? Anyone with these fans that can give me a testimony? Thanks.

 

Every time the fan comes on it will cause an amp draw that will create more resistance in the alternator, which will put more dragf on the engine. BUT, the fan(s) will not be on all the time, where the stock fan or fan clutch is always being a drag.
If the fans were on all the time then the stock fan would be more efficient. This would be due to efficiency losses in the alternator and the fan motors. The mechanical fan does not have these losses.

I guess it would come down to how much your fan(s) will be on.

 

I recently upgraded to a 180amp alternator and put in 2x 16" derale tornado fans (18amp draw each) They do dim the headlights slightly when the kick on but that is not very often unless im sitting at a stop light or have the air on in which case they come on quite often as currently setup.

 

I found that the electic fan kit that Mike Troyer sells (superchip guy) uses 18.2 Amps per fan!

Now on a stock 130 amp alternator you will notice when the fan kicks in but the fan may not draw the full 18 amps all the time. Remember as the fan has less resistance (going down the freeway with the air blowing though the radiator at 65 mph) the fan can turn just as fast without working as hard therfore not taking up as much power. Also when driving at a fair rate of speed the cooling from the air passing though the radiator is normally enough to where the fan may not need to run at all but can kick on and off when needed. Plus theres 2 fans for when you tow etc. So if you see a fan kit with 1 fan, stay away not a good idea with the bigger engines.

On the other hand the stock fan with the clutch is going to sap power even when the clutch is not fully engaged. The effecency of the electic fan really shines on the highway not nessarily around town. But when you step on it the fan isn't stealing that enetic energy away from you, because as the RPMs of the engin increase so does the speed of the fan and so does the resistance on the fan.

I have heard many say that the electic fan kit (generalized term any electic fan kit) will give you around a full 1 extra MPG increase in fuel economy and can give you up to 12-15HP gain (fan not on as the alternator will pull a little bit of horse power when the fan(s) are on) VS the stock fan. And I have seen what the electic fan looks like, there is about and extra 8-10 inches of space that the engine compartment has between the radiator and the block, I would think that this would help with the air circulation under the hood. Plus if you install a rack there you can keep your food warm as it is close to 200 degree air at that point...

 

Thanks for all the input. Still not sure whether I will do this or not, but I sure like the idea of a little extra puch from my 5.4. Thanks again.

 

My truck is supercharged but and in addition to adding the electric fans, I moved the air temp sensor to before the bypass for the blower. I wanted to see what kind of difference it made. I gained 19hp at the rear wheels.

 

Ford has been using electric Fan's on various vehicles for some time now. The Mustang's have had it since 1994 and I've had no problems from my '95 GT Convertibles stock electric fan and the stock 130 amp alternator. Well.... I've replaced the alternator once but with over 180K miles I've had pretty good luck with the car.

What size alternator do the Supercrew's come with anyway? I never really thought to look that one up.

 

The SuperCrews come with the 130 AMP alternator stock. You could add a bigger one (up to 200 I belive) but unless your running a lot of electrical equipment or have a huge stereo system (yes they can draw a lot of power) then there should be no need to upgrade it.

 

Yep, 130amp is what my 02 screw has, however after adding the blower and its fuel pump, electrix fans (18amp each) and my stereo I figured I should get one a tad bigger. Stereo alone can draw about 110amps.