[White_SS/RS]

That's a good question. The entire system was designed to maintain a ~200 water temp. What usually happens with lower temp thermostat is that the engine will only run at those lower temps during mild street use and at low ambient temps. This is mostly due to the fans being inoperable at the lower temp. To remedy this you would need to modify the fans circuit since the ECM only allows the fans to be programed to 190 or 195 if I recall correctly. Otherwise the engine will just run at the temp its designed for and the thermostat remains in a continuous open cycle. I'm sure if the cooling capacity or efficiency of the system is increased as well as modifying the fan circuit you would see benefits from it.

I'm curious though if there is enough airflow to offset the amount of heat generation during track use to push the temps lower than what is normally seen ~220. That would be assuming you started with a lower temp in the first place. Its my guess that it would just stay where it normally nulls out in the ~220 range. I mean, the system already displays its incapacity to maintain the 200 let alone bring it below that.