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Oil cooler line diameter size

Can Can

Pusher Man
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I have a little question about oil cooler lines and ID(Inner Diameter) measurements. Is there such a thing as going TOO BIG? Could an oversized line affect the ability for the cooler to efficiently process the oil? I realize that too SMALL of a line could be a bad, but what about something that is too large?

As well, what size and kind of aftermarket tubing are some of you running to your oil coolers?
 
I use Earls own brand, just the black rubber stuff not braided. I use 3/8" i/d for motor, trans and power steering coolers.
Can't see any problems with a larger dia. but no advantage either as it will still have to got through the fitting either end. I've also just fitted thermostic by-pass valve to the motor and trans coolers. Warms up much faster now.
 
I believe that a line that is too big will allow the fluid to flow so fast that it doesn't stay in the cooler long enough for the cooling process to work properly. An example of this is pulling the thermostat out of a car with a high flow water pump will make it run hotter. Same theory anyway.

Anyone believe differantly?:ears:
 
I have heard that an engine oil cooler needs larger lines than a tranny cooler because of the volume of oil being pumped is a lot higher. How much larger is enough I don't know. I'd look at aftermarket oil coolers and get a better idea of what size lines are often used...and go from there.

Rene
 
JEBSR said:
I believe that a line that is too big will allow the fluid to flow so fast that it doesn't stay in the cooler long enough for the cooling process to work properly. An example of this is pulling the thermostat out of a car with a high flow water pump will make it run hotter. Same theory anyway.

Anyone believe differantly?:ears:


Eh, not so sure I buy that... For a couple reasons...

1 - I'm not so sure the larger volume of a bigger line equates to the oil moving "faster".. moving more yes, but the speed would still be controlled by the actual oil pressure of the motor and the passage leading to the entry of the cooling system..

2 - No matter the size of the line, the cooler is still the limiting factor... If you had a 3/4" i.d line feeding a 3/8" i.d cooler, it'll only flow what the cooler can allow for..

Personally, I generally think bigger is better.. Just increasing the overall capacity with that larger line is a big plus imo.. I know when I get around to redoing mine, I'll be running some #10 steelbraided.. I would guess the factory equivelent is a #8, but it could be 10... Seen plenty of setups that are running #12. My only issue with that big a line is routing becomes that much more difficult...
 
The engine oil PSI has nothing to do with flow speed or line size. You could have 1/8" lines or 24" lines and they would both have the same pressure.
The volume that the lines can flow is what you need to be concerned with. A 1/8" line can't flow as much volume as a 24" line can.
In water line systems that I have installed before they need to increase the contact time with the Chlorine so they up size the water line for a certain footage from say 6" to 24" and this slows down the water to let the chlorine contact the water longer to kill the bad stuff. The pressure in the 24" is the same as the 6" and the volume of water flowing into the 24" and out of it back to the 6" is the same. It just takes longer for the 6"line to fill the large void that the 24" pipe is.

You need to run lines large enough to handle the GPM that you have from the oil pump. The lines need to be strong enough to handle the oil pressure that your engine produces.
I would find a line that handles the GPM you have and then up size some for a safety factor. I would think -8 or -10 would be good sized line.
 
vol

i think the volume would go up , but the psi would go down . think of it as throwing a hotdog down a hallway .
 
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