I run a TNT as well, but I run my dual cooling the "conventional" way.. two into the manifold.
I'm not 100% sure on my screw settings, but I know the bottom is closed. i think the middle is closed too, and the top is like 1/2 or 5/8 open. However, I am always skeptical when people swap water screw settings since the adjuster screws are not tapered like a carb screw, so how accurate really is the turn number???
And it all varies by water pressure (set-up)...[/QUOTE]
This is very true, I reallized this more so this past week. I had a blaster mod chamber on my sons SJ and I did 2 things:
1) Added true dual water (2 lines in from pump) instead of one coming in and splitting.
2) Changed the chamber from Blaster Mod to SJ Mod chamber.
I did not touch the water set screws and I ran more water to the Blaster Mod chamber than the SJ Mod as they seemed to run hotter. The boat ran great on bottom, but then flattened out considerably right at mid and through top. I am about 90% sure this is due to too much water to the pipe. I am 1.25 turns out on top screw, .500 turns out on center and closed on bottom. I think the major difference is the water pressure added by the actual dual water.