do u need the same pressure radiator cap as the standard unit?
My ae92 uses a 0.9bar cap, if i am to replace this, can i use a higher or lower pressured cap???
Yeah, whats the point? You dont need to use the same one but if you use higher pressure then there more chance of your radiator/cooling system failing due to excessive pressure, and if you use a lower one then it might start spitting coolant out when it doesn't need to.
trd makes a 1.4 bar
and toda makes a 1.7 bar
less pressure is bad
the reason it presurises to to raise the boiling point of the fuild inside the system
so more presure keeps the fuild from boiling under higher temperatures
as vvega stated, a higher pressure cap allows the cooling system to run the coolant at a higher temp before boiling.
so its really only going to be worth it in a race application where theres a lot more heat. if you were running a race car and had problems with the coolant boiling then a higher pressure system may help.
if the coolant system is in good condition then there shouldnt be any problems.