This brings up several theory questions...maybe it's time for some real world testing...I think everyone agrees the bigger the rad the better, so how about a 1.4 T'bird @ 1.85V, Autozone #398219 heater core with 2 - Panaflo H1A's, Eheim 1250 with reservoir as a standard test system...that should make the WB the weakest link (sorry, couldn't help myself
Test #1 - Standard nanoblock
Test #2 - Custom nanoblock with 1/2" fittings and a 3/4" to 1" internal bore for max flow
Test #3 - Custom block with 1/2" fittings that feed a large channel that breaks down to 4 - 6 smaller, straight channels then back to a large channel for max flow and area of water contact
Test #4 - Standard Maze 2 with 1/2" fittings
Then, maybe, repeat the same tests with the Eheim 1048 for lower flow.
Una, you up for the task?