So, got my GT500 pump kit from DOB installed on my 4.6 with Kenne Bell and VMP triple pass HE. Used the bypass option for the pump. Pump is super quiet.
I was surprised to see no movement in the reservoir, and I thought at first the pump was air-locked. Right now, I have the system such that it runs down hill from the IC to get to the pump. In between, it tees off for both the supply and return lines to the reservoir. Both points on the reservoir represent the highest points in the system - fluid actually has to climb uphill through two feet of hose to get to the supply entrance of the reservoir). So, maybe the fluid is taking the path of least resistance (bypassing the reservoir), especially considering all the restrictions with the KB? I also have the reservoir tank pretty full (higher than the return line entry), so it is possible there is movement under the surface.
I took it for a spirited run. It was 60 degrees out. AITs stayed 100-110. Would climb to 115ish under boost or closed throttle, then quickly come back down when light on the throttle. So I guess its working, though I did wonder if the cool air being sucked into the intake could keep it that cool even if the pump was locked up. Jason (DOB) says no.
Note, the fluid in the reservoir still felt very cool to the touch even after the run. The engine coolant, in contrast, was HOT.