Thanks for the info guys. Yea I probably couldn't get away with a non-thermostatic plate. When the time comes for the oil cooler I will go ahead and get a thermostatic plate.
The over heating issue has been a pain. Last track day, out of nowhere the car is in the red. I never had overheating issues before, it usually even idled cool in 80 degree temps. After getting the car in, the radiator was ice cold and the engine was boiling over so our first thought was that the thermostat wasnt opening. I had another session in an hour and we didnt have the appropriate tools (other than a hammer)so we just ripped out the thermostat to get me going. We refilled and bled the system, after which the radiator got hot and the engine temps were running cool. I went out again and after 2 laps it was way in the red. Brought it in and that was it for the day. A week later, I put the car on jack stands (front) and filled the system until it came out of the high point vent. Turned on the car and it started to over heat, radiator was cold again.
Later that day I got some help and we tried again. Finally got water to flow through the system and the radiator started getting hot. At this point we would watch the coolant reservoir and when the water would begin to well back up into it, we would open the high point vent to let air out and close it quickly. (The temps were below normal at this point since it had no thermostat.) We poured a little more water into it and continued to vent the system each time it wanted to well up. However this went on for 10 - 15 mins and the air never stopped coming out of the high point vent. At this point, we assumed that air was getting into the system since we had been burping the system continuously for that long. I saw no leaks on the ground. I also went back and did a compression test which I don't know what to think of. Prior to the track day it was 170, 165, 153, 165 and after it was 161, 159, 161, 159. So the plan now is to rent a pressure tester for the cooling system.