AC performance mod
#436
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I fail to see how a system with a 16 lb. cap can have more than 16 lbs. the radiator is connected to the engine through the 2 rad. hoses. when the pressure in the rad. is 16lbs, the pressure in the rest of the system is 16lbs. there`s no logical or physical way there can be different pressures in the system at the same time. you say it has been proved time and time again, post up the articles so we all can see. the pressure in the block, the head, and radiator, will always be the same, unless you can change the law of physics.
#437
Here is the short version....LOL
The Water pump generates suction and the result is positive flow or volume into the block, the water flow is evenly passed up through the head gasket which has smaller passages to be sure the water flows evenly from the block up through the head then forward within the head and out the T-Stat or bypass dependent on whether the motor is hot or cold. At RPM the pump makes a lot more volume and taking the smaller passages in the head into account the water has no Ware to go so then it generates pressure and it has been said the weakest point is the rear core plug on the motor.
I understand this but the 75 PSI is still surprising??..
The Water pump generates suction and the result is positive flow or volume into the block, the water flow is evenly passed up through the head gasket which has smaller passages to be sure the water flows evenly from the block up through the head then forward within the head and out the T-Stat or bypass dependent on whether the motor is hot or cold. At RPM the pump makes a lot more volume and taking the smaller passages in the head into account the water has no Ware to go so then it generates pressure and it has been said the weakest point is the rear core plug on the motor.
I understand this but the 75 PSI is still surprising??..
#438
Advocate of getting the ban button used on him...
LarnDart hit it! That is how I have explained it to people in the past. You can go into more detail about how the smaller passages in the block and head are the cause for this increase in pressure and the overall volume and flow characteristics of the radiator are the reason for two different pressures n the system.
#439
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The Water pump generates suction and the result is flow or volume into the block when the water reaches the end of the block it passes up through the head gasket which has smaller passages to be sure the water flows evenly from the front of the block to the back of the block through the head and out the T-Stat or bypass dependent on weather the motor is hot or cold. At RPM the pump makes a lot more volume and taking the smaller passages in the head into account the water has no Ware to go so then it generates pressure and it has been said the weakest point is the rear core plug on the motor. I understand this but the 75 PSI is still surprising??..
#442
jtamulonis,
Suppose these was a restriction (orifice) that limited flow downstream of the water pump output. Could there be a pressure differential across this orifice?
Assuming there could be a pressure differential, could this pressure rise cause additional stress on a freeze plug which could then be expelled?
Thanks,
Dale
Suppose these was a restriction (orifice) that limited flow downstream of the water pump output. Could there be a pressure differential across this orifice?
Assuming there could be a pressure differential, could this pressure rise cause additional stress on a freeze plug which could then be expelled?
Thanks,
Dale
#443
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jtamulonis,
Suppose these was a restriction (orifice) that limited flow downstream of the water pump output. Could there be a pressure differential across this orifice?
Assuming there could be a pressure differential, could this pressure rise cause additional stress on a freeze plug which could then be expelled?
Thanks,
Dale
Suppose these was a restriction (orifice) that limited flow downstream of the water pump output. Could there be a pressure differential across this orifice?
Assuming there could be a pressure differential, could this pressure rise cause additional stress on a freeze plug which could then be expelled?
Thanks,
Dale
#445
jtmulonis,
First, thanks for your help in understanding this issue. I tend to agree that it is likely that the downstream cross sectional area in the aggrgate is at least the same size as the water pump output. It is interesting that the freeze plug ejections have been reported to occur (as I recall) when the engine is warming up and not later. This could mean the viscosity of the coolant has an effect, or there is localize expansion differential at the plug (block warm (bigger ID), plug cold (smaller OD) and/or the is a pressure wave through the system. Or something else.
However, I don't understand you assertion that the pressure is the same on both sides of an orifice. There seem to be plenty of systems that calculate flow based on the pressure differential across an orifice.
Ffrom http://www.mcnallyinstitute.com/13-html/13-12.htm
Approximate flow through an orifice 13-12
There are several reasons you might want to install a restrictive device, or orifice in a piping system.
* To create a false head for a centrifugal pump, allowing you to run the pump close to its BEP.
* To increase the line pressure.
* To decrease the flow through a line.
* To increase the fluid velocity in a line.
The equation for flow through an orifice is a simple one to understand. Only the units are somewhat awkward.
Q = AV
Q = The flow in cubic feet per second (ft3/sec).
A = The area of the orifice in square feet (ft2).
V = The velocity of the liquid in feet per second (ft/sec)
Thanks,
Dale
First, thanks for your help in understanding this issue. I tend to agree that it is likely that the downstream cross sectional area in the aggrgate is at least the same size as the water pump output. It is interesting that the freeze plug ejections have been reported to occur (as I recall) when the engine is warming up and not later. This could mean the viscosity of the coolant has an effect, or there is localize expansion differential at the plug (block warm (bigger ID), plug cold (smaller OD) and/or the is a pressure wave through the system. Or something else.
However, I don't understand you assertion that the pressure is the same on both sides of an orifice. There seem to be plenty of systems that calculate flow based on the pressure differential across an orifice.
Ffrom http://www.mcnallyinstitute.com/13-html/13-12.htm
Approximate flow through an orifice 13-12
There are several reasons you might want to install a restrictive device, or orifice in a piping system.
* To create a false head for a centrifugal pump, allowing you to run the pump close to its BEP.
* To increase the line pressure.
* To decrease the flow through a line.
* To increase the fluid velocity in a line.
The equation for flow through an orifice is a simple one to understand. Only the units are somewhat awkward.
Q = AV
Q = The flow in cubic feet per second (ft3/sec).
A = The area of the orifice in square feet (ft2).
V = The velocity of the liquid in feet per second (ft/sec)
Thanks,
Dale
#446
Registered User
No need to wait - we tested several years ago... at rated RPM there's over 200 lbs. of ejection pressure on each block plug (~ half that on the "soft" plugs in the head).
Cylinder 5 & 6 run hottest, so plugs are more likely to come out back there due to localized steam pocket formation.
Cylinder 5 & 6 run hottest, so plugs are more likely to come out back there due to localized steam pocket formation.
#447
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No need to wait - we tested several years ago... at rated RPM there's over 200 lbs. of ejection pressure on each block plug (~ half that on the "soft" plugs in the head).
Cylinder 5 & 6 run hottest, so plugs are more likely to come out back there due to localized steam pocket formation.
Cylinder 5 & 6 run hottest, so plugs are more likely to come out back there due to localized steam pocket formation.
#448
i know im bringing a thread back from the dead here....
but lets say you have a bad blend door, would this remedy that problem? you would think so b/c if you cut the hot water off then there is no heat to blend with
but lets say you have a bad blend door, would this remedy that problem? you would think so b/c if you cut the hot water off then there is no heat to blend with
#449
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im curious to see if anyone that has actually done this mod had any kind of negative side affect to their engine/heater core? im going to guess no.
I went out and bought a pusher fan from jeggs (becool euro 2" thick model) and will be installing it this weekend.
I also bought 3 ball valves and 2 T's so I can by pass the heater core but still have coolant flowing like normal no matter what position it is in.
I went out and bought a pusher fan from jeggs (becool euro 2" thick model) and will be installing it this weekend.
I also bought 3 ball valves and 2 T's so I can by pass the heater core but still have coolant flowing like normal no matter what position it is in.