Do you need the fan shroud?

[joel w]

J3pz: That is a good option and will also free up some extra power in the motor but may not be as effective as stock.

To demonstrate how a fan shroud is effective, Take a old (junk) 12v 3" muffin fan from an old pc and plug it in to 12 volts and feel the air flow moving through the fan.

Now cut the shroud off of it and re check the flow of air. It is now totally useless as an air mover..All it will do is make a mess of the surrounding air..

Edit: Now want to see something really cool, Find a cardboard tube that is 1/6th of an inch bigger than the muffin fan blades. 3" tube should work. Now put the fan inside the tube and apply 12v and hold on to it good...

This is now a "ducted fan" and it will not only moves air, but it will create thrust