Originally Posted by Moparrbust
Let me first say that these are my thoughts and opinions...and not Brians.
If the tank truly separates the regular cooling system and the s/c cooling system then there shouldn't be ANY coolant in that tank(water cools better than coolant/antifreeze). Coolant is for keeping the water from freezing. On top of running 100% water in the tank, I believe, there should be a drain **** of some sort in the bottom to drain out enough water to be replaced with ice when necessary. Again all my thoughts and they may be horribly incorrect...read at your own discretion.
This is similar to my thought, I only see one inlet for fluids/ice etc... meaning whatever you put in will involve both systems. And unless you have a drain valve/isolated compartment in the tank how could it not all mix and therefore be full of antifreeze? I'll wait for Brian to explain before speculation, I'm sure he's thought of that!
Edit: or drain the entire system and refill to water everytime you want to go to the track? Because day to day antifreeze does more than stop you from freezing up, it raises the boilover temp( as water boils at 100 c and ethylene glycol boils at 198 c) and acts like a heat exchanger + provides lubrication and anti corrosive properties.