Originally, my heater worked GREAT connected to the OEM SBF intake manifold on my '93 5.0L. It was the OEM hard lines that run front to back across the top of the black.
I'm currently finishing my new engine install and had to re-plumb the heater hose from the new intake.
I ran the new engine and allowed it to cycle several times, the fan kicked on about 190*+ and shut-off at 180*, but the heater never blew hot air. It took a long time for the hose going to the heater to warm up. The radiator hose heated up much quicker and got warmer.

I ran my heater hose to the port on the thermostat housing and the Water temp sensor is plugged into the port on the intake. I think the problem is this port is after the thermostat and not getting much circulation.
How have others solved this? Do I need to move the heater hose to the intake? (How? A T-fitting on the intake for temp sensor and heater? What fitting would I need for this?? (part # / link please).
A picture would be greatly appreciated.

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