Just looking at the UMP housing and filter this makes no sense to me. The openings in the housing and the surface area of the filter all appear to be larger than the stock air box and filter.
All test’s (if I can call them that) where done with the stock air tube, stock exhaust and the Predator on the 120 tune.
To start off, when I installed the UMP, the filter minder would not fit using the straight hose that comes with it. I found a piece of bend water hose and cut it down to fit.
Once everything was installed I took the truck for an easy drive. Checked everything out, no problems. I then went for another drive. This time I put my foot to it. When I got back home I noticed that the filter minder had pulled down to the first notch. Over the next couple of weeks I checked the filter minder and it was always pulled down to the same spot. Yes, I did reset it every time I checked it. Today I pulled the UMP off and installed the stock air box and filter. Drove around easy and hard. The filter minder didn’t move. Well…maybe it was the water hose extension that was causing the problem? Bought a barbed splice and installed that and the water hose between the filter minder and the box. Went for another drive. Again the filter minder didn’t move.
To me this indicates that the UMP is restricting the flow. Am I wrong? Did I miss or do something stupid?

I have heard of some AFE's doing the same thing ....


Your theory makes since but it might just be initial demand not overall loss of flow ...





Mac

I've got 18K one one with no problems. From the pics, it appears that yours has more open area than the one I'm running. Does it feel like the truck is more or less responsive? If it feels more responsive, I'd say it's the filter minder or possibly something wrong with the tube inside the housing. I'd give Cliff at UMP a call.

Ox