I had an electric pump and fan on the street and the car would run cool around town but would climb to about 220 as soon as I got on the highway.
Now being a tech for over 30 years told me it was a flow issue,air and or water through the rad. I took the electric pump and fan out and installed a belt drive pump and 1 to 1 pulleys with a 5 blade viscous drive and viola!!! 180 degrees on the highway. Now thats with a 180 stat and a simple factory type deal with no shroud even.

Gus