hi, here is all you need to know...
i had a swirl pot on my car... it actually caused more problems than it was worth. on my R33 in my drift car, i have no water hoses coming off the block at all besides the one from the side of the thermostat housing that i have linked to the top outlet of the head near the front of the engine. this is my bleed point. turbo is hooked up as normal.
once i read the service manual on the RB25det thoroughly, i found the biggest mistake everyone makes when filling the coolant system in these engines....
you have to fill it extremely slowly. the specified filling speed is no more than 2L/min. this means you must take 5 min to fill it up! trickle speed....but doing this means there are no airlocks!