rad cap

[briggers]

just a quick question what does a different rad cap do. always thought but never actually asked.

saw someones topic and saw they had a 1.3 bar rad cap?

[Mikey Jay]

Not sure, but I have the TRD rad cap, tis shiny and therefore worthwhile ;)

[StarletRick]

the pressure rating on a rad cap is the release presure, ie, the pressure within the cooling system required to open the cap and bleed the pressure off into the overflow tank.

all a higher pressure cap does is raise the needed pressure to open the valve.

[Asad]

its to do with the radiator water pressure....i.e. if you mod the car etc n at high speeds lots of water pressure builds up and the std cap may not be able handle it n burst.....i think??

[StarletRick]

lol ^^

not quite.

its a bit more scientific than that. water under pressure has a higher static boiling point.

the higher the pressure, the higher the boiling point.

thermal transfer depends on the differential between the surface producing the heat, and the surface taking the heat.

so in theory, the higher temp in the rad fluid has a greater differential temperature than the air flowing through the rad. resulting in better cooling.

sounds fancy eh?

reality is, unless you rape your car around a track, youll never get the coolant hot enough to release the stock cap. if you are, then theres something wrong with your car.

[briggers]

blimey. didnt know there was that in depth explanation out there just for a rad cap.

how do you know these random things lol