Since there has been a clear trend from 180 on up to 207+ coolant temperatures think about experimenting there. Since there is good older evidence that 140 - 160 is best for peak high rpm power, those higher coolant temps were adopted to increase fuel economy at lower cruise rpms.
185 thermostats have been the specified rating since at least the 40's. Nothing to do with economy, everything to do with decreased engine wear not to mention oil sludging.
A 180 thermostat doesn't being to open until 3 or so degrees of its rated temp- so 177. Full open temp is 15-20 degrees above the rated temp. Most engine wear happens on startup and is not because of a 180 vs 205 thermostat.
You would be wrong. Go peruse the image I attached to my prior post. Begins opening at 157-162 degrees, fully open at 183-187 degrees. Uses the same thermostat as the pre-79 v8's and the values were confirmed this last weekend with my IR gun.
The rated temperature is the fully open temperature.
You reference a paper that shows a temp for the beginning of opening at about 160 degrees, and fully opened at 180. That is a 160 stat.
IR guns are notoriously inaccurate. Not sure how you could get a temp on the thermostat itself through the housing anyway.
"The rating listed on the thermostat is the point at which the device begins to open. This is not the full open temperature, which is typically 15-20 degrees above the listed temp. For example, a 180 degree thermostat begins to open within three degrees of 180, so 177 to 183."
"Most late model thermostats are calibrated top open around 195 to 200 degrees F. The thermostat should be fully open about 20 degrees F higher than its rated temperature for maximum flow, and should maintain engine temperature in the 200 to 230 degree range."
