Originally Posted by ckovach
I've heard this assertion before, but I don't see how a lower thermostat will make any difference in most locales except in the winter time. Assuming the t-stat is wide open (as it normally is in the hot summer months), it doesn't matter if it opens earlier at a lower temperature or not...the engine is going to run at the temperature the cooling system can achieve whenever the t-stat stays wide open, regardless. If it's running over 180, a 180 t-stat or a 160 t-stat or no t-stat are all the same. The thermostat is to regulate the cooling system's water temperature to ensure that it isn't too cold, not that it's not too hot.
With the supercooler, the engine will run hotter because you've robbed some of the cooling capacity of the cooling system by placing the supercooler in front of the condensor and radiator. You would do better to go to a bigger or more powerful fan IMO (or you could just turn off the AC for that matter, but who's gonna opt for that...).
The reason you can potentially get away without a reservoir on the charge air cooling system is that once you add the supercooler and separate it from the engine cooling system, it may never get hot enough to require much expansion surge; the rubber hoses take up the minimal expansion without overpressurizing the system. Probably fine for a daily driver, but I question whether you might still need some extra surge if you're racing the car or running it really hard in hot weather. With this in mind (and being in southwest FL) I opted for BrianBrave's extra tank.
If you do a lower thermostat and reprogram the cooling fans the cars run cooler. My car never see's higher then 180-185 engine temp, with cooler engine temps there is less heat transfer into the intercooler fluid if you keep the same resevoir. If your splitting the tanks then I don't think it is as important, but if you run the supercooler I don't think it is a good idea to raise engine temps up another 8-10* degrees. If you go that route I would lower the engine operating temps. There are several different ways to go, I still run the LET cooler because I don't like the idea of blocking the radiator and A/C condensor, and because we get stuck in traffic alot I figured may as well cool off the whole system. My A/C runs ice cold in bumper to bumper traffic.