That guy is doing all sorts of crazy things for the IDI world. The fans they use on OBN generally come out of ford vehicles like taurus, thunderbird, aerostar, or anything else that came with a 3.8L or larger engine in a passenger car. The ford OEM fans are made by Siemens (german equivalent to america's general electric) and are said to be quite reliable. I think they use brushless motors but I'm not positive, however I do know that siemens is a world leader in commercial duty, high efficiency motors (brushless or otherwise). They are typically good for about 4500CFM or up to 6000CFM if you are lucky enough to find one that came from a crown vic.

Dual fans are usually used and when done right, overheating extremely unlikely

Just for the hell of it, I took my radiator fan off this winter to see if there was any change in MPGs. City driving went up from 13 MPG to 15 with no change in driving style. Highway didn't gain quite as much, but I didn't do so much highway driving this winter, so its hard to say. I have a brand new quad core radiator that is a bit of an overkill for my truck and how I used it so not everyone will be able to get away with that kind of stunt.

The warmup time is what was mostly responsible for the 2 MPG drop with the fan on. With electric fans, that problem is eliminated and from Agnem's reports, they hardly ever come on at all unless its very hot out and they are working the truck hard. My fanless experiment seems to agree with that because I never ran warmer than normal with the fan off. A/C would not work at stand still though.

 

2 mpg? sweet. i can honestly say that i have only heard my fan blowing hard once, and that was towing 10-11 thousand and two axles over the coquihalla. the electric fans would be a pretty good idea for our winters. when it got to -30 this year i had to let my truck warm up for 1/2 hour. i used almost the same amount of fuel warming up as i did driving 45 minutes to work. when my windstar dies im gonna rob the fans. (it shouldn't take too long, the van has 350,000 on it)