Question...what is the normal running temp for a 1972 340

190* i believe ....... my problem is when I get out on the highway it starts to run hot .....like all the way over to the hotline after only 10-15 min at 65-70 mph .......soon has I slow down it immediately starts cooling down ....like in the first mile at 30 mph .....i added a aftermarket gauge and it confirmed what the stock gause was doing ...... new pump ( flowkooler ) new lower hose ( with spring ), clutch fan, temp sending unit, Radiator rodded out ( questionable of the guy that done the job) checked motor in different areas with a laser temp gun seems to be consistent with the 230 deg the gauge reading at the time