Craig,
i just installed it today and we won't be camping for at least another week or so (I need to get the hitch installed in my new truck first).
I'd estimate it to be about 3/4 of the air movement. It keeps the outside vent cover open about 3/4 of the way. Doing a search for the range hood using the fan motor manufacturer shows that it is made by Elixir (also known ad Jensen). The rated air flow is 85 CFM (
http://www.dyersonline.com/p-1221-el...ange-hood.aspx). Since the computer fan is rated at 79 CFM, I figured it's close enough to work. There are other computer fans of about the same size that spin faster and move more air, but they are also louder by 5-10 DB and my focus was on quiet.
Also, if you don't want to replace the fan, I have seen other mods online to control the speed of the motor in the range hood. It involves adding a resistor in line.
one other side effect is that these fans draw a lot less amperage...0.24 Amp vs the original fan's 1.6 Amp. This is a good point for anybody that boondocks.
Fred