In all my years of driving and working on old mopars, since 1993, the most consistent I've ever had any engine run was when I ran a 195 thermostat. I've never seen one run at 160 when I installed that thermostat , they just don't stay that cool. Normally I run a 180 and out of 3 cars with a 180 they still stay at about 190. So the next one I install will be a 195.