Yes, exactly. I’ve found my bone stock 996 to have barely adequate cooling at speeds 45mph and below. It’s a question of airflow for sure, because 45mph and below requires little power.

 

Did an apples to apples comparison today. Same road, same driving, same ambient temperature. With clean A/C radiator and the mod, temp is a good 10 degrees C lower.
I stopped at the top of the pass as first time and non of the fans was running, last time all fans was running at full speed incl the engine bay fan. Idle oil pressure was higher and the temp needle indicating a good 10 degrees C lower.

During the drive the engine only passed above 90 degrees C on the steep serpentine road where speed is low and engine load high. Rest of the time it stayed like glued at the 80 degrees mark.