UDP are pointless IMO but my dual 16" efan setup sucks at A/C unless you are moving forward. Sitting still it just pumps out mild air, I would not recommend it for extreme hot states.

 

The hp it takes to accelerate a rotating mass goes up exponentially compared to accelerating a mass like the body of the truck/car. The theory is good and it does work.

If you change the rear gears to higher ratios without putting bigger tires on, it might make sense to use ud pulleys to slow down the accessories to their previous speeds.

 

you must have bad fans. before my clutch went out on my compressor my dual 16s pulled LOTS of air and kept my A/C really cold. After 10 minutes in the Florida sun I would have to turn it down because I would get chills.

 

Do you have the plastic radiator cover removed? I removed mine to do some work and went for a drive with out the cover on, no cold air as the air flow goes around rather than through the condenser.

I have dual 16" fans and it is very hot here.....48* coming out of the vents.

 

good point. there are 3 shrouds designed to move air through the condenser. one on the bottom (rubber-like material), next one is a small set of rubber-like material on each side of the condenser and the last one is the radiator aesthetics cover

 

fans are brand new with maybe 3K miles on them just like everything else. Hell the truck/motor doesn't even have 11K miles on her. E-fans just don't work that great at idle for long periods of time. Once driving they get really cold but that's about it.

 

I gain better gas mileage and added hp.

 

efans, IMO do more than power. Opening the hood, the lack of a mechanical fan and shroud reveals more of the engine. So my hood looks more "cleaned up" plus it looks mean with those two bad boys strapped to the front. I love looking at them everytime I pop that hood