Ditch the Thermostat?

Sounds like your radiator might be plugged up inside or outside, No flow some where
Did this start when you changed intakes ?

Thanks for the replies everyone. It already had the Manifold when I got it. Wife bought it as a gift so I am still deciphering everything so I don't really know the mechanical history of it.

Radiator being clogged is something too. I have flushed it several times. But when squeezing the upper radiator hose I'm not getting that surge of flow feeling you would expect.