I'm planning on buying a thread in style sending unit for my electric fan setup as my radiator probe style unit is not working. Theres two options I can choose: a 185* ON/170* OFF or a 200* ON/180* OFF. I have a 180* TSTAT installed on a 360 magnum engine. Its just a street car two as well. Also, This will be installed on my intake manifold on the opposite side of the temp gauge sending unit (right by the upper radiator hose) if that makes a difference.