Actually - apart from being careful not to exceed the maximum pressure of the radiator you won't need to worry about that part of the system. The reason a car's cooling system in pressurized is to increase the = boiling point of the water (antifreeze/antiboil can also be added to increase it = further) The radiator cap also serves as pressure relief as the coolant expands/cont= racts. >>> A.B.Pearce@RL.AC.UK 06/19/02 03:37AM >>> >does anyone know about the active surface of such a >car radiator and the thickness of the lamella (between >air and water)? or does anyone have any data of such a >radiator, that help me calculate how much power I can >'destroy', depending on the airstream and temperature >difference? remember it needs to take a reasonable amount of pressure, what is a radiator cap, something like 15 PSI before = it releases pressure? =20 -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email listserv@mitvma.mit.edu with SET PICList DIGEST in the body