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Old 05-15-2009, 03:58 PM   #1
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Default 20PSI Radiator Caps

thoughts?

Will running one cause coolant to push pass the coolant rings on the engine? Or will the rings be fine?






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Old 05-15-2009, 10:37 PM   #2
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Don't do it.
At that high cooling system pressures, you get LOTS of leaks!


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Old 05-15-2009, 11:22 PM   #3
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Originally Posted by RETed View Post
Don't do it.
At that high cooling system pressures, you get LOTS of leaks!


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Internal or external?

Since you're running the same AFCO radiator as me, do you have a preference for the cap you run on yours?
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Old 05-16-2009, 03:54 AM   #4
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Yeah, pressure is way too high. Id imagine you'll find a few external leaks but it'll put unneeded pressure on the coolant seals. No need to up the pressure. Upping the pressure raises your boiling point. Raising the boiling point is beneficial on really hot running engines. We know these engines don't like to run hot. Standard 1 bar cap.... I'm using a 13 psi cap, will be fine.
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Old 05-16-2009, 04:21 AM   #5
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I couldn't tell if there were internal leaks, but I saw a LOT of external ones!
You can get one of those cooling system pressure testers and see for yourself.
Everytime I tried over 20psi, coolant started leaking from the damndest places!


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Old 05-16-2009, 08:30 AM   #6
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that's really peculiar to me. I've been running the 20 psi bar for the past few days and have been able to isolate and fix all the external leaks. When I idle the temperature gets up to regular temps but then will immediately start to cool. The E-fan will actually kick off which is something it never did with the old radiator and pressure cap. My Engine temps have been cooler too. Whether that's from the radiator or benefits of the cap I don't know. In the mean time I'll pick up a new radiator cap and see if I can't find me a recirculatory tank some where.
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Old 05-16-2009, 09:45 PM   #7
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I don't see how a higher PSI cap would increase the cooling effects of the other parts, but I could be wrong.

As for the recirclating tank..... you got access to a TIG, build your own. Unless you want me to start calling you names
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Old 05-16-2009, 11:58 PM   #8
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Originally Posted by TitaniumTT View Post
I don't see how a higher PSI cap would increase the cooling effects of the other parts, but I could be wrong.

As for the recirclating tank..... you got access to a TIG, build your own. Unless you want me to start calling you names
Lol, you're going to have to start calling me names. I don't have access to the TIG right now. (Internship)

It was my understanding that a higher PSI rating allowed thermal transfer easier through the aluminum. I too, could be wrong... but I will do a google search and see what comes up.

http://www.stewartcomponents.com/tec...ech_Tips_2.htm

That's about the most helpful link I could find in the five minutes of searching.

My theory is this: As the engine heats, the heat is then absorbed by the coolant. As the coolant takes on that heat it begins to become less dense, and by effect become less able to absorb the heat coming from the engine. As the coolant gets to the boiling point, it builds pressure. This pressure forces the heat from the engine to continue to be absorbed at a specific rate. Once the peak pressure of the cap is reached, it vents it to the recirc tank and the process starts all over again.

The theory stays the same for high pressure (20 PSI, which I assume is absolutely safe for the engine since Pineapple racing tests their cooling systems to 20PSI to check for leaks). Since the pressure is higher than stock the boiling point of the coolant is raised, which allows heat to transfer from the hotter source (the engine) to the still liquid coolant. Once that is then pushed to the radiator more molecules are packed to the cooling fins thus rejecting the newly absorbed heat, ergo a cooler engine.

This is of course just a theory, and I do not have the funds as of right now to fully test it. But if some one does test it I would like to hear the results.

I had tons of external leaks when I first started using it. Everything from an adapter being pushed out, to a hose bursting (it was old and already worn). Yet as soon as I fixed all those leaks it seemed to work quite well.

I have to drive back down to blacksburg tomorrow because I forgot a few important things for the internship, so I'll report back on the temps of the 13lbs (.8 bar). From what I noticed just on this trip up to Culpeper my temperatures were slightly hotter than what I was used to driving around town with the 20lbs (1.something bar), though temps never seemed to stay around 200F for very long and usually fell sharply after the hill climbs back down to 180-190F.
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