Hi my 87 300d temperature was running at or below 80 & the heat barely worked. It also has the 14 head. It's got 250k, 2nd owner, & always been taking care of. So I out an 80 degrees Wahler thermostat in it & now it's running 3/4 the way to the next line(assuming that's 100?).

Is this normal or too hot? Someone told me to put a 71 degrees one in but I would like the heat to work. It never teaches 100. I tried to see if it would go there but couldn't. The fan clutch works fine. Very worried due to the 14 head.