Actually, it does help cool the engine faster by creating airflow through the engine bay. This can significantly reduce under hood temps, especially where the engine bay is fairly closed up. My 85 Porsche has dual fans, with one that runs after key off when the temp is high enough. The engine bay is pretty tight, and the cooling fan does a very good job of cooling everything down quickly. Might not be as effective on the truck, but it will still help.
I've also not had any problems with battery run down, but it also has a good charging system...
E~

 

What exactly is a variable rate controller? Where might someone find one?

 

Flex-a-lite has them. It comes with the 294 and 295 dual fan kits or you can purchase it by itself.

The Mark 8 is a good fan to use if you're on a budget, but it does not cover the entire radiator. I've been running the 295s for years and no problems. They're dual 13.5" pullers and they're mounted in a shroud that covers the entire radiator. The VSC ramps the fans speed up slowly so it doesn't tax the electrical system. It can run a 2 speeds, 60% or 100%, to maintain the tempreture. It also has an input to where the fans will turn on when the AC compressor is running and also with a manual on switch if so desired.

The 295s can move up to 4600 cfm and the 294's can move as much as 6000.

 

Here is a site I ran accross a while back, it has some good diagrams.

Page Title

 

I run Flex-a-lite fans on both my trucks, both of which are controlled by a variable speed controller with a temp probe pushed in the radiator fins for temp control. My gasser and my diesel. I haven't gotten to drive my F-150 long distance yet, but it doesn't seem to have any cooling issues. I drive my diesel every day and the fans on it use the same controller and motors as my 294 universals I put on my F-150 and it has been working great on my diesel.

The main reason I went to e-fans was not for mileage or power. I don't think there is much to be had as far as that goes, but I can say I noticed a slight difference in response on my diesel after the switch. I switched to e-fans on my F-150 so I can turn the fans off when I get in some water when I'm wheeling and I switched to them on my diesel basically b/c everyone said e-fans couldn't keep it cool, so I'm out to prove otherwise. LOL

 

Also the 94-00pm ford contour or mercury mystique 3.8l v6s have dual fans that move 4500cfmin on high. I have been pulling tons of them for 30$ a pop it can't be beat

 

they are a controller that slowly ramps up the power to the fan(s) so they only spin as fast as required to cool the engine as opposed to simply on or off.
i went with the FK-85 here:
Constant Temperature Controllers and Accessories



it's a little pricey yes.but there are advantages.less draw on the alt,without the high amp turn on spikes,and much more constant temps than with the relay type i had first.which is better for the engines head gaskets because your not drastically changing the temps up/down so quickly.i also noticed the fans just work at keeping it cooler easier than with the relays too.it was worth every penny.i couldn't be happier with the thing.i dunno how things work there now,but it was just Brain i think who builds them as he goes,likely a side job.so order in advance if you want one.it can take a while.

 

I didn't see much about A/C in this thread. You really want the fans running when the A/C is on or you will only get minimal cooling at a stoplight.

That Felx-a-lite variable speed controller has an input from the A/C to run the fans when the compressor is running. It can also be done with another relay as shown in some of the diagrams.

 

I've got that with my Flex-a-light. Been thinking of putting a switch inline so I can disconnect it in the winter. Comes on with the defrost but I'm thinking it's not really necessary.

 

I spoke to that over on page 1, A/C wired to come on auto when air is on.

 

about time that someone on here talks my lingo. how is the 294. is $425 a good price any notice in HP!

 

Not to jack this thread but I was wondering how many of you with the efans have upgraded to the 3G for there efans?

 

i run a single 16in e-fan w/a spal vary control unit capable of running dual fans if the need occured w/ a/c over ride. the single fan moves 2300 cfm and is mounted in a sheet metal housing w/ 12 louvers to help air flow when the fan is not running. i was thinking of using a hole saw and making holes instead of louvers but, the louvers look nice and i also used a orbital sander on the sheet metal to give it a satin look when the fan is mounted and it came out pretty well when all was said and done. my setup to me runs good and have no problems at all. i was also thinking of changing the fan and running 2, 12in fans just to see how cool it would be when running.

 

Any pics traxx?

 

if you leave the fans running after shut down it only really cools the coolant in the radiator and through convection cools the motor down a little faster not enough to make a difference. wireing two fans so that if one fails the other can keep going is a good fail safe being the odds of both fans failing at the same time is pretty dang rare. I had a s10 with a 406 in it and the duel tarus fans kept it super cool and if it did start to get a little warm i had a toggle in the cab to kick fans to high could watch the temp gauge drop the worked so good. something to think on is surface area that the fans are pulling from? if you zip tie the fans to the radiator it will work and can get the job done but if you go get a cooky sheet that close to the dimension of radiator the fans pull air through the whole radiator which cools things evan better. Ive cooled big block motors and hot rat motors with the tarus fans Ill stand by them before any aftermarket fan Plus the have two speed rates so if you were to get fancy you could have 4 different levels of cooling power
ok ok i went a little evil with the last idea but you got to admit that would be cool