How hot is hot?

1....Nawhmbah whaon......check accuracy of the gauge. Many ways to approach that. Let it warm up with pressure cap off and monitor with a "candy" or other thermometer, "what have you" Borrow or buy an infra red. Tape a probe to the bottom of the top hose, and insulate it temporarily around the probe with rags and tape

2....Try a different thermostat. 190 is fine but "buy a good brand." I realize that is difficult nowadays

3....Post photos of the setup

4....What specific conditions does it do this, IE highway, idling, low cruise, med cruise?

5...Where is timing set and what have you for a curve?