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if you're talking about the radiator cap, it simply holds more pressure.

at higher pressure, it takes more heat to overwork your coolant system. it's a bit more complicated than that, but that's about it.
 

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djrez4 said:
if you're talking about the radiator cap, it simply holds more pressure.

at higher pressure, it takes more heat to overwork your coolant system. it's a bit more complicated than that, but that's about it.
c'mon man....give us the physics!!! the suspense is killing me, that makes total sense, and actually was what a was suspecting to be the case, but can't quite figure out exactly how this principal works (not meaning the cap specifically), nor the value of having higher pressure in the cooling system. it's kind of like fifth grade math class here now....to get credit you must show your work.
 

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aw man...do i hafta? :rolleyes:

more pressure raises the boiling point of the liquid in your cooling system. you actually want your coolant to boil, just not throughout the system.

the coolant circulates through the engine and boils at the hot spots. the gaseous coolant then carries the heat away and condenses away from the hot spots, cooling them and preventing bad things from happening. then the coolant gets pumped to the radiator and cools off to begin the process again.

it's the same concept as adding salt to boiling water to get noodles to cook faster. in this case though, you're changing the boiling point by pressure, not chemical alteration.

do i get full credit now? :D
 

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you get a 97%.

only partial credit for the incomplete explanation of the coolant's boiling/recondensation. (the higher pressure also allows the coolant to come back to liquid quicker, thereby being more effective of a coolant because it is in liquid form longer in the cycle) -5 pts.:D

+2 pt bonus for the salt analogy. very nice;)


dR :p :p :p :p
 

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Has anyone ever told you guys that you know a little bit too much about cars? This amount of knowledge can't possibly be healthy!
 

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*bows* thank you, thank you! :D

if i was employed, i wouldn't have as much time to learn about all this crap. :D
 

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pace said:
PV = nRT

V, n, and R will remain constant. So, if your cap can hold more pressure, then the coolant can have a higher temperature without 'boiling'.

-Pace
well garsh....ya make it sound so boring and sterile! :D

hey pace....i have upgraded my suspension and tires....wanna go for a drive? :D
 

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Ideal Gas Law??

I would think that wouldn't apply to the situation so well... I thought that only applied to gases... Because if you think about it... if n and R are constant... if you increase pressure on the gas, the temperature would have to rise because volume cannot decrease (Incompressible liquids). Ugh, nevermind, I'll look it up. =)
 

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djrez4 said:


well garsh....ya make it sound so boring and sterile! :D

hey pace....i have upgraded my suspension and tires....wanna go for a drive? :D
Very cool. Now when do you move to stage-4?

I ran the Golden Gate with my buddy on his R-6 a few weeks ago. Some nice new sticky tarmac on the lower portion of the canyon.

-Pace
 

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Re: Ideal Gas Law??

cobra117 said:
I would think that wouldn't apply to the situation so well... I thought that only applied to gases... Because if you think about it... if n and R are constant... if you increase pressure on the gas, the temperature would have to rise because volume cannot decrease (Incompressible liquids). Ugh, nevermind, I'll look it up. =)
You sort of have it right. The STi cap allows for higher coolant temps because it can withold more pressure. That's all.

-Pace
 

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pace said:
PV = nRT

V, n, and R will remain constant. So, if your cap can hold more pressure, then the coolant can have a higher temperature without 'boiling'.

-Pace
its funny how equations relate to other fields. in finance, those same acronyms would mean

the present value of an investment (PV) - number of periods (n) times the periodic rate (r) times time (t)

that isn't true, but it's still neat.

in fact, the present value of an investment = the future value/(1+r)^n

<shrug>

dR
 

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pace said:


Very cool. Now when do you move to stage-4?

I ran the Golden Gate with my buddy on his R-6 a few weeks ago. Some nice new sticky tarmac on the lower portion of the canyon.

-Pace
i know! they repaved the whole thing!

SBC-iD is coming next week....then the real upgrades begin! now if only i had some income to support my habit. where did i put that job...........
 

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[PlatinumWRX]Uhhh.. guys, you should really move it to PM[/PlatinumWRX]
 
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