Random Overheating?

[MRice]

To get this out of the way now its not a BHG compression tested/no coolant in cylinders. Its not the heater core because i have a brand new one installed by Toyota. The turbo has no leaks and the coolant system has no leaks either (compression tested) But still my car will overheat, it wont even do it at all at first but 5min into the drive it skyrockets for some random reason then as soon as i brake hardish or turn the car off for a second it goes right back to normal
and then i can push it rediculously hard and no change in heat and i mean ever i had my spool gauge maxed no change in heat or anything so what the hell is going on? it only seems to be doing this when it starts cold though... which leads me to believe a hose is tempidly plugged or something and thus it dosnt get coolant to a certain part fast enough? Any thoughts?????????? Temp gauge? Rad is 1 year old