OK, I was just curious. I didn't know if anyone had ever tried one of those handheld wind speed meters you see for hunting or whatever. A LOT of very good info here. I just built a box 20x20x30 with my old belt driven furnace fan inside with 3 sides having 25x16x1 filters. I only have one Filtrete 1500 Ultra Allergen per side, looks to be a MERV 11 according to a site I just found.
I should probably add a couple more, or find a smaller micron filter. I plan to just duct tape around them to seal, they're just there for test fitting. Kids were wanting dinner, so I had to stop there.
As for where it will be located, I have it sitting in the 'bed' of my CJ5, as I am going to be sanding the wheel wells to smooth the fiberglass I just laid last week. Cannot get it any closer!