1 MCP350 Pump or 2 MCP350 Pumps?

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lostiam2

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Would 1 MCP350 pump with a modified Alphacool Laing top, which I already drilled out the top inlet hole for a 1" barb be enough to power the following loop, or would I have to use 2 pumps?

I will be using the following items:
1x Swiftech APOGEE cpu block
1x Danger Den 680i chipset block for the SB
1x Danger Den A8N Maze4 chipset block for the NB
1x Danger Den 8800 GTX block for the video card
2x Swiftech MCR220-QP radiators

Thanx for the advice!
 
it's fine. I'm fairly confident that it is. (But I can't buy ANY watercooling crap from anywhere until my PayPal account verification issue gets solved, so I'm not going to give a definitive answer.)

EDIT: Why are you running two MCR220-QP rads?
 
I'm using 2 rads because everyone's been saying that the 8800 GTX runs really hot, and I'm going to overclock my E6600. I figure this way the 2 rads would be able to cool everthing thing down using 7v fans for low noise. Plus my new Thermaltake Mozart case has room for 2 radiators on the back.
 
no room for a 3x120mm? the pressure drop from two 2x120mm rads is going to be much higher than if you just use one 3x120mm. I highly doubt there would be a noticeable temp difference. To be honest you would probably be fine with just a single 2x120mm but the triple is a little more[H]ard. :D
Edit: lostiam... don't steal bandwidth, host your own pics please.
 
Justin_Diduch said:
no room for a 3x120mm? the pressure drop from two 2x120mm rads is going to be much higher than if you just use one 3x120mm. I highly doubt there would be a noticeable temp difference. To be honest you would probably be fine with just a single 2x120mm but the triple is a little more[H]ard. :D
Edit: lostiam... don't steal bandwidth, host your own pics please.
Click to expand...

You could always run the 2 radiators in parallel. It will lower the pressure drop, but also lower the flow rate through each radiator.
 
Erasmus354 said:
You could always run the 2 radiators in parallel. It will lower the pressure drop, but also lower the flow rate through each radiator.
Click to expand...

That's a good thing, having a lower flow rate will give the water more time to dump heat into the air and result in even lower water temps.
 
I didn't know where to mount the triple rad, since there was just room for 2 double rads on the back of the case. So I can just use one MCP 350 modified pump and have the two 2X120mm rads hooked up in parallel? How do I go about setting it up in parallel? Do I use T connectors , and then how do I join them back together again to go into the pump? Thanks in advance for the input.
 
I'm not sure if one mcp350 with the modded top will be enough for two 2x120 rads, the full cover block, and the chipset cooler. It probably wont hurt to try with one now and if you dont like your temps get another one, but imo I think you probably need two.
 
madmat said:
That's a good thing, having a lower flow rate will give the water more time to dump heat into the air and result in even lower water temps.
Click to expand...

then how do you explain the lower thermal resistance a radiator achieves when flowrate is increased?
 
n00btard said:
then how do you explain the lower thermal resistance a radiator achieves when flowrate is increased?
Click to expand...

How do you explain a car overheating when the flow restriction of the thermostat is removed allowing the water to flow through the radiator too quickly?
 
madmat said:
How do you explain a car overheating when the flow restriction of the thermostat is removed allowing the water to flow through the radiator too quickly?
Click to expand...

madmat, it isn't a simple issue of flow rate. When you decrease the flow rate, sure the water is in the radiator longer, however you are decreasing turbulence inside the radiator which worsens the transfer of heat to the radiator from the water. Also in a fully serial loop it doesn't help at all because while the water will be in the radiator longer, it will also be in the waterblocks longer.

Overall it is usually best to have a higher flow rate because that will lessen the temperature difference throughout the loop, and more often than not provide the best performance from the radiator.
 
Erasmus354 how should I set the 2 radiators up to run in parallel? Should the output from the pump go to a T-branch then to the 2 radiators and then:
1 radiator -> vga block
1 radiator -> cpu block -> sb block ->nb block
then join it back together with a T-branch to go back into the pump?
 
madmat said:
How do you explain a car overheating when the flow restriction of the thermostat is removed allowing the water to flow through the radiator too quickly?
Click to expand...
Erm, where do you come up with this? This is just not the case, it seems you don't know much about what thermostats in cars do. Engines run most efficient at a set temp, usually around 195 degrees F or so. Once the water temp reaches the thermostats rated temp, it opens up fully. It will not close (or start to close) until the water cools down a LOT, about 20 degrees or so. A car with no thermostat will not overheat (unless there is another issue) it will just take a LONG time to come to proper operating temp. The Fed's don't like this because a cold car produces much more pollution.
 
madmat said:
How do you explain a car overheating when the flow restriction of the thermostat is removed allowing the water to flow through the radiator too quickly?
Click to expand...


That's not the job of the thermostat. The thermostat regulates flow to the the engine to keep it at about 200'f. It's a wax compound that melts at 183'f (or so) thus allowing more fluid to the car radiator when temperatures exceed this value.

When the car is very cold. Very little, if any, coolant is actually making it's way to the radiator. If the engine does not meet it's optimal temperature, excess hydrocarbon is produced during combustion, putting more stress on the environment and the car it's self. Mileage will drop very fast on the car.

Thermostats, when stuck open (allowing full coolant flow) are very dangerous to the car's health. In very cold climates, the cabin of the car will probably stay freezing, and the engine's block may even refuse to turn over.
 
The hell it's not the job of the thermostat. Take an automotive class and learn a bit more or, call a mechanic. Why do you think that they sell these for use in cars without thermostats? They take the place of the thermostat and slow the flow of the water so that it can pick up and release heat.
 
Those reducers are for reducing the amount of water that enters the radiator, tuning performance... I've never seen a car run without a thermostat (road-capable), and it's highly regarded as a stupid practice to do so. Having no thermostat is for the crazy people with heavily modded performance vehicles...

From what I know, restrictors are used only to prevent cavitation in the coolant system (from a high speed centrifual pump) or to generally fine-tune water speed...

Yes, thermostats also slow down the speed of water, so it stays in the radiator longer... BUT, explain why it lets more coolant through (opens up) when the engine gets hotter...
 
I didn't realize my question would end up opening a can of worms for debates, interesting reading though. I still have no clue as how to hook up the 2 radiators in parallel, any suggestions?
 
lostiam2 said:
I didn't realize my question would end up opening a can of worms for debates, interesting reading though. I still have no clue as how to hook up the 2 radiators in parallel, any suggestions?
Click to expand...


Well, it's quite simple... Get 2 Y splitters... And split the water flow, then rejoin it. It's alot of work for such a marginal benefit...

Ys are here
 
You don't get much pressure drop from a radiator. For the most effective way to cool in a serial loop with 2 Rads I would route PUMP> Rad> Cpu> NB> Rad>Video>SB> back to PUMP. If you want to increase the velocity add a second pump just before the second rad. Adding the second pump is good for redundancy also. If one fails (like my last one did) there is no chance of losing any of your system (it will just run hotter).
 
madmat said:
The hell it's not the job of the thermostat. Take an automotive class and learn a bit more or, call a mechanic. Why do you think that they sell these for use in cars without thermostats? They take the place of the thermostat and slow the flow of the water so that it can pick up and release heat.
Click to expand...

Funny thing is that I ran my old '86 Firebird's 305 without a stat for a good year. Ran at about 150-160*F during the summer. Was a bitch to warm up during the winter. What finally killed that motor, though, was I blew a belt, which stopped the waterpump's spin. Waterpump survived and I used it on the 350 that eventually went in that car before I blew the tranny.
 
[BRO]Alaskan;1030457875 said:
You don't get much pressure drop from a radiator. For the most effective way to cool in a serial loop with 2 Rads I would route PUMP> Rad> Cpu> NB> Rad>Video>SB> back to PUMP. If you want to increase the velocity add a second pump just before the second rad. Adding the second pump is good for redundancy also. If one fails (like my last one did) there is no chance of losing any of your system (it will just run hotter).
Click to expand...

The most effective way to cool a serial loop is actually whichever way is easiest and uses the least amount of tubing. The water temperature doesn't change a whole lot throughout the loop, and its ability to absorb heat changes even less throughout the loop. Bottom line, the components later in a loop are not getting worse cooling just because they are last.

(technically yes they are, but it is so small that it would fall within the range of error on most thermometers)
 
Wait!

2 MCP 350 with the alphacool Hardwareluxx dual laing top-

its money but pretty slick
 
nikhsub1 said:
Erm, where do you come up with this? This is just not the case, it seems you don't know much about what thermostats in cars do. Engines run most efficient at a set temp, usually around 195 degrees F or so. Once the water temp reaches the thermostats rated temp, it opens up fully. It will not close (or start to close) until the water cools down a LOT, about 20 degrees or so. A car with no thermostat will not overheat (unless there is another issue) it will just take a LONG time to come to proper operating temp. The Fed's don't like this because a cold car produces much more pollution.
Click to expand...

Wrong. A car most certainly WILL overheat with no thermostat. I've known it to happen to several of my old racing buddies, and not all jsut in their "highly modified performance vehicles."

The job of the thermostat is to do two things, one is what you said. The one you're overlooking either by choice or simple unknowing is to restrict flow. The water pump of a car is capable of moving MASSIVE amounts of water very very quickly, and the hoses (usually what, ~2" inner diameter average let's say?) are as well. The thermostat creates a restrictive barrier so that the water flows through the radiator slower.

Want proof? Go to the auto parts store and buy a radiator for a dodge ram and a honda civic. One will be considerably larger than the other, but the larger one will have a lot more "rim" area around the actual plunger/opening of the Tstat. This is because making the opening too big would allow TOO MUCH flow.

I've also had mine stick open on my dakota when I used to bracket race it a lot, all is well till you start sitting in some traffic. Overheating like all hell, which would be impossible with your above explanation.

Just trying to set a couple facts straight :cool:
 
Arcygenical said:
Yes, thermostats also slow down the speed of water, so it stays in the radiator longer... BUT, explain why it lets more coolant through (opens up) when the engine gets hotter...
Click to expand...

The reducers are for exactly what he's saying they're for. Seen them used many times as well.

As for the question at the end of your post, it's a relatively simple answer that most people sort of overthink I guess you could say. A normal car (not counting any 8 second strip cars)'s radiator is almost always overkill for what it really NEEDS to stay cool. They have to be built this way because most people are morons when it comes to cars--they never check any fluids and expect the car to "just run". Doing this gives them a bit of headway so hopefully they get their mind off the cell phone for a second and look down and see the temperature guage on the rise, rather than already pegged at well past critically hot. A car thermostat isn't just open or close, with no in between. As you yourself stated, it's a wax that melts and resolidifies repeatedly while driving. Thus, there are different degrees of "openness" that it maintains at all times. If it's only half open, there may just be something of a "really fast trickle" coming through it, but that might be plenty of flow to keep the car cool on the way to work at 7am. This isn't because of the amount of flow, its because the radiator is, again, more than the car really needs, and is doing an adequate cooling job even if only running at 50% duty. The same car goes driving on lunch hour at noon when it's hot as hell outside (I live in houston, hot as hell ;)). The air going through the radiator is hotter, and thus the under-hood temps and thus internal engine temps are hotter. Step up the flow a bit to compensate. Higher volumes of water will always cool better as they are less prone to heatsoak (yes, engines can get MASSIVE heatsoak just like too small a loop on a WC'ed computer that's at high load for a long period of time).

So in short, the fact that the thermostat opens up more when the engine hotter is due mostly in part to radiator size. But at the risk still of sounding preachy, which I'm not trying to do, a car WILL MOST CERTAINLY overheat with too much flow going through the radiator. The guy below said his car was fine for a year... I ran mine about 6 months that way too, it's not that bad on the engine, it's only bad on the egos of the emissions hippies. But a combination of HOT weather and not much airflow through the radiator, and your stuff is gonna be getting HOT.
 
Wwwow... Necropost :p

I'm almost tempted to prove this once and for all... If only I had another good thermometer...
 
waltherone said:
The reducers are for exactly what he's saying they're for. Seen them used many times as well.

As for the question at the end of your post, it's a relatively simple answer that most people sort of overthink I guess you could say. A normal car (not counting any 8 second strip cars)'s radiator is almost always overkill for what it really NEEDS to stay cool. They have to be built this way because most people are morons when it comes to cars--they never check any fluids and expect the car to "just run". Doing this gives them a bit of headway so hopefully they get their mind off the cell phone for a second and look down and see the temperature guage on the rise, rather than already pegged at well past critically hot. A car thermostat isn't just open or close, with no in between. As you yourself stated, it's a wax that melts and resolidifies repeatedly while driving. Thus, there are different degrees of "openness" that it maintains at all times. If it's only half open, there may just be something of a "really fast trickle" coming through it, but that might be plenty of flow to keep the car cool on the way to work at 7am. This isn't because of the amount of flow, its because the radiator is, again, more than the car really needs, and is doing an adequate cooling job even if only running at 50% duty. The same car goes driving on lunch hour at noon when it's hot as hell outside (I live in houston, hot as hell ;)). The air going through the radiator is hotter, and thus the under-hood temps and thus internal engine temps are hotter. Step up the flow a bit to compensate. Higher volumes of water will always cool better as they are less prone to heatsoak (yes, engines can get MASSIVE heatsoak just like too small a loop on a WC'ed computer that's at high load for a long period of time).

So in short, the fact that the thermostat opens up more when the engine hotter is due mostly in part to radiator size. But at the risk still of sounding preachy, which I'm not trying to do, a car WILL MOST CERTAINLY overheat with too much flow going through the radiator. The guy below said his car was fine for a year... I ran mine about 6 months that way too, it's not that bad on the engine, it's only bad on the egos of the emissions hippies. But a combination of HOT weather and not much airflow through the radiator, and your stuff is gonna be getting HOT.
Click to expand...
As a full blown mechanic and a Junior/Senior level Mechanical Engineering student (taken Thermo I, Thermo II, Heat Transfer)

The car does not over heat because the flow through the radiator is too fast.
The faster the better for heat transfer.

If your car overheats after the removal of the thermostat, it's because of a completely unrelated result. Most likely an air pocket forms in the water pump due to the agitation created by a 'too-fast' flow, causing it to cavitate and not pump effectivly. I can't tell you the exact reason, I'd have to examine the car. But it's definetly not because the water is flowing through the radiator too fast.


BTW, I have personally run three different cars (91 Toyota Pickup, two Nissan 240sx's:
one with a ~270hp aluminum turbo motor, other with a 155hp iron block motor) with and without thermostats. None had any overheating problems without the thermostat, and ran as expected: with drastically reduced coolant temperatures.

The thermostat is there to regulate temperature (it does so by restricting flow).
It's not typcially there to restrict absolute flow as suggested by some in this thread
However, there could be issues with poor cooling system design in some cars that results in air bubble formation/migration to the water pump when the flow rate is too high.


Moral: You wont see any cavitation issues or bubble formation in a PC water cooling system. The faster the better. (to a point. you dont want to be pumping the water so hard that the pump contribues more heat then the faster flow rate helps the rads.)
 
okashira said:
As a full blown mechanic and a Junior/Senior level Mechanical Engineering student (taken Thermo I, Thermo II, Heat Transfer)

The car does not over heat because the flow through the radiator is too fast.
The faster the better for heat transfer.

If your car overheats after the removal of the thermostat, it's because of a completely unrelated result. Most likely an air pocket forms in the water pump due to the agitation created by a 'too-fast' flow, causing it to cavitate and not pump effectivly. I can't tell you the exact reason, I'd have to examine the car. But it's definetly not because the water is flowing through the radiator too fast.


BTW, I have personally run three different cars (91 Toyota Pickup, two Nissan 240sx's:
one with a ~270hp aluminum turbo motor, other with a 155hp iron block motor) with and without thermostats. None had any overheating problems without the thermostat, and ran as expected: with drastically reduced coolant temperatures.

The thermostat is there to regulate temperature (it does so by restricting flow).
It's not typcially there to restrict absolute flow as suggested by some in this thread
However, there could be issues with poor cooling system design in some cars that results in air bubble formation/migration to the water pump when the flow rate is too high.


Moral: You wont see any cavitation issues or bubble formation in a PC water cooling system. The faster the better. (to a point. you dont want to be pumping the water so hard that the pump contribues more heat then the faster flow rate helps the rads.)
Click to expand...

I supposed the air pocket thing could be it as well, but like I said, I've known several people who have had cooling issues with the removal of a thermostat, all of which occurred in low speed (traffic-like) conditions. An air pocket's problems shouldn't be discriminating in their choices of conditions for overheating (and if they are, this would make them very consistent air bubbles, since it's always in low-speed conditions :p).

I know you're probly thinking the cars would've overheated regardless in those low speed conditions, but these are guys that have had some of these cars for years and years and have done numerous Tstat changes on them without issue. I think the theory of too much flow was derived from the fact that there would be too many coincidences if it was only caused by an air pocket.

Gah, whatever. All I know is, I've had nothing but bad luck with running with no thermostat. I also had cooling problems in our hot houston summers when my Tstat was stuck open on my dakota (little 300-310hp @ crank aluminum block, since you listed your block types/power levels), so I won't ever be doing it again without one of the restrictors in place (which btw, cured the problem right up on mine and at least one other guy's car).
 
waltherone said:
I supposed the air pocket thing could be it as well, but like I said, I've known several people who have had cooling issues with the removal of a thermostat, all of which occurred in low speed (traffic-like) conditions. An air pocket's problems shouldn't be discriminating in their choices of conditions for overheating (and if they are, this would make them very consistent air bubbles, since it's always in low-speed conditions :p).
Click to expand...
Why wouldn't the state of the air pockets change with engine conditions? e.g. rev up the motor, the air pockets will flush to another location with the sudden rush of water.
I know you're probly thinking the cars would've overheated regardless in those low speed conditions, but these are guys that have had some of these cars for years and years and have done numerous Tstat changes on them without issue. I think the theory of too much flow was derived from the fact that there would be too many coincidences if it was only caused by an air pocket.
Click to expand...
No, I fully belive that the cars ran fine in traffic with the tstat in. I should have stated that I have heard of cars overheating with a removed tstat before; I'm sure it happens.

Gah, whatever. All I know is, I've had nothing but bad luck with running with no thermostat. I also had cooling problems in our hot houston summers when my Tstat was stuck open on my dakota (little 300-310hp @ crank aluminum block, since you listed your block types/power levels), so I won't ever be doing it again without one of the restrictors in place (which btw, cured the problem right up on mine and at least one other guy's car).
Click to expand...
Guess I should have listed the head material, too. (more important for cooling.) all my cars have had aluminum heads.

I do think it's unusal that a car will overheat with the tstat removed, and I have heard of it occuring before. I did some thinking and it may actually be possible that a 'too-high' flow though the radiator reduces the cooling capacity.

First; computer water cooling rads, a/c condensors and many other types of heat exchangers are designed with a very different goal in mind when compared to a car radiator. PC water cooling radiators are designed to dissipate as much heat as possible from as low temperature differential as possible. More importantly, they are designed to bring the coolant as close to ambient temp as possible, thus they have a single pipe that undulates thru the array of fins - a unit of water can take only one path thru the radiator and gradually decreases in temperature as is passes thru the radiator.
This is not the case for a car radiator. A car radiator has the freedom to operate at a very high temperature differential and only needs to cool the water a couple of degrees - certantly no where near ambient. Thus, they have a very open design - a unit of water is not forced to travel along a tube, it can take any path and flow freely thru the radiator. It's more like a 'bath.'

I wonder - where are the inlet and outlet in relation to each other on your Dodge radiator?
It's possible that an overly fast flow rate causes the water to 'jet' through from the inlet to the outlet, leaving the rest of the water mosly stagnent and cool, thus killing the effectivness of the radiator. See ms. paint fig. 1:
untitledlg2.jpg
(fig.1 )

It seems very unlikely, but in any case you may be right. But it's not somthing that could happen in a PC water cooling rad (or most other heat exchangers for that matter) because the water is forced to take a specific path.

in summary, possible reasons for a car overheating with no stat:
1.) formation and migration of air bubbles to temp sensor or water pump.
2.) ruined distribution of flow thru head/block due to air bubbles(an air bubble can actually BLOCK flow to parts of the head/block.) or fluid dynamics implications.
3.) messed up flow thru the rad (see fig. 1)

In any case, none of this can occur in a pc water cooling setup.
 
Lets look it at another way. In air cooling, the radiator(aka heatsink) is in direct contact with the heat source. So with air cooling you need these things for lower temps.

1. Lower ambient temp
2. More air flow over heatsink/radiator (more = more contact and heat transfer)
3. Bigger surface area

Same principles works with water. Except, in watercooling, the primary cooling surface is not in direct contact with the heat source. Air is still the ultimate place your heat gets dumped to. External radiators have larger cooling surfaces and are more efficent in transfering heat to air. The water acts as a conduate. Fast/slow flowing water is like copper versus aluminum heatsinks. The faster the water flows the faster your loop reaches an equilibrium temp, thus less hotspots. If the water sits in the radiator longer, than yeah, it's temp will drop more. But, on the otherside, the water will sit on top of your CPU/GPU longer and that will get hot faster than a radiator cooling.
 
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