Collapsed fuel sock..
 

Found this weekend. I have been troubleshooting a drop in FP over 6000 RPM for a bit and when I pulled the DW3000 out the inlet was collapsed and black on the outside. The new Mazda part we had in our spares has a nice big bulge over the inlet.
Picked up 5 PSI at idle and problem solved. I'm guessing the DW3000 dumping through our bypass regulator and the older designed sock was to much for it.
Vince