12VDC Pump Max Head Pressure Test Data

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Petra

Gawd
Joined
Jul 8, 2003
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Hey everyone! Some of you who also frequent the XS Forums may remember my quick head pressure testing in this thread a couple of weeks ago... Well, I decided to expand upon it and test more pumps that I happen to have sitting around. Below is the data that I collected--PLEASE make sure to read the notes about the data.

The Data:

MAGII LE: (at 11.98V) ~3psig (6.92' -- 2.11m)
3psig ~= 83.03" water column at 4 deg. C (using the same conversion that Lee at SystemCooling does--1.0" = 0.03613psig)

CSP-MAG: (at 11.98V) ~2.8psig (6.46' -- 1.97m)
2.8psig ~= 77.5" water column at 4 deg. C

AqX 50Z-DC12: (at 11.93V) ~5.2psig (11.99' -- 3.66m)
5.2psig ~= 143.9" water column at 4 deg. C

Laing D5 (Swiftech MCP655): (at 11.89V) ~6psig (13.83' -- 4.22m)
6psig ~= 166" water column at 4 deg. C

Laing DDC+: (at 11.88V) ~8.5psig (19.6' -- 5.98m)
8.5psig ~= 235.26" water column at 4 deg. C

Laing DDC+ w/unmodded Alphacool top: (at 11.87V) ~8.2psig (18.9' -- 5.76m)
8.2psig ~= 226.96" water column at 4 deg. C

Notes:

My results for both the 50Z and CSP-MAG basically match those obtained by Lee over at SystemCooling but, for some reason, the MCP655 I tested [apparently] ended up putting out a lot more head pressure than it was supposed to (based on Swiftech's specs and Lee's testing--1.2psig over Lee's result). Curious, I repeated the test numerous times with two different MCP655's and I came up with the same result every time. One of the MCP655's is new and the other one that I used is from a batch that we received in November of 2005 (it was pulled from the water cooled cardboard box display machine).

So, yeah, aside from the somewhat puzzling data from the D5, everything else seems to be pretty good. :)

...and here's a quick photo that was taken while testing the CSP-MAG:

TESTCSP_MAG.jpg


Also, incase anyone is wondering and/or confused by all of that extra tubing, I modified one end of my waterblock testing setup to carry out the pump head pressure testing. I used the red-handled shutoff valve, that's in the right half of the photo, to isolate the test-pump from the rest of the loop (this way, I'm only dealing with the pressure gauge).

Thoughts? Comments? Suggestions?
 
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Justintoxicated said:
so should I sell my D5 and get a DDC? :)

Thanks for sharing your results with us here at [H].
Click to expand...

No, selling used D5 will get you around $50 ~ $60 bucks and DDC+ comes with 3/8" fitting only and you will need to mod to 1/2" or buy new top which you will need to spend about $60 ~ $80 more to get DDC+ w/ Modded Top. Beside D5 is a powerful pump so no need to upgrade it, for first timer looking for new pump then DDC+ will be the best choice
 
What is the difference between the DDC, DDC Pro, DDC+, and DDC Ultra?

Also, why does the DDC+ with the Alphacool top perform worse than the DDC+ without? I thought the whole purpose of the Alphacool top was to improve performance?

I would like to know the change in performance of the DDC with Alphacool top as a result of drilling out the inlet as some have suggested.

Also, what is the impact of adding the Alphacool reservoir on top of the Alphacool top?

Cheers,
- VR.
 
virtualrain said:
What is the difference between the DDC, DDC Pro, DDC+, and DDC Ultra?

Also, why does the DDC+ with the Alphacool top perform worse than the DDC+ without? I thought the whole purpose of the Alphacool top was to improve performance?

I would like to know the change in performance of the DDC with Alphacool top as a result of drilling out the inlet as some have suggested.

Also, what is the impact of adding the Alphacool reservoir on top of the Alphacool top?

Cheers,
- VR.
Click to expand...

DDC, DDC Pro, DDC+ are the same 10w version pump and DDC Ultra is 18w version pump. DDC pumps are original with standard 3/8" fitting, and DDC Pro/ DDC+ pumps comes with modded 1/2" Top but still 10w version pump. DDC Ultra pumps comes with modded Top but 18w version
 
Hard911 said:
DDC, DDC Pro, DDC+ are the same 10w version pump and DDC Ultra is 18w version pump. DDC pumps are original with standard 3/8" fitting, and DDC Pro/ DDC+ pumps comes with modded 1/2" Top but still 10w version pump. DDC Ultra pumps comes with modded Top but 18w version
Click to expand...

Thanks. Any pointers to data on the peformance with or without the alphacool res attachment?
 
The after market tops result in a loss of head pressure, but a very positive increase in the flow rate curve when using the top outlet/side inlet configuration. Unless you can't afford to get an after market top, you should almost always make sure to get one with whatever DDC variant you're using.
 
Hard911 said:
DDC, DDC Pro, DDC+ are the same 10w version pump and DDC Ultra is 18w version pump. DDC pumps are original with standard 3/8" fitting, and DDC Pro/ DDC+ pumps comes with modded 1/2" Top but still 10w version pump. DDC Ultra pumps comes with modded Top but 18w version
Click to expand...
Actually, that's not entirely correct... "DDC Pro" is merely Alphacool's name for the 10W Laing DDC with their custom top and "DDC Ultra" Alphacool's name for the 18W Laing DDC+ (DDC2-TPMP) with their custom top.

As for the performance of the Alphacool top... well... The Alphacool top allows for the use of standard 1/2" barbed G1/4" thread fittings and provides a substantial boost in flowrates when using the top inlet (basically, it eliminates the 90-degree bend immediately before the pump's inlet). The Alphacool top's weakness is that they left the inlet channel the same size as it appears in the stock DDC top (a wider inlet channel (about 9 or 10mm ID) yields an even greater boost in the pump's max flowrate). How does this apply to the data that I posted? Well, that's rather simple, really... I was testing the pump's max head pressure, not the pump's max flowrate.

When using any of the custom tops, you'll see a substantial increase in flow and a slight decrease in max head pressure (but it's not like this pump doesn't have head pressure to spare :rolleyes: ). By design, the Radiical top will incur the largest loss in head pressure, whereas the Alphacool top should incur the smallest (as it most closely resembles the stock Delphi top). Personally, I'm going for something in between those two with my design--though, I have yet to reach the prototyping phase.
 
Petra said:
The Alphacool top's weakness is that they left the inlet channel the same size as it appears in the stock DDC top
Click to expand...

Did you mean to say "outlet channel" here? I mean with the Alphacool, no one uses the side inlet right but you must use the side outlet? Am I confused?

EDIT: I think you are referring to the inlet as per the mod described here?
http://forums.bit-tech.net/showthread.php?t=85428

At any rate, I'm interested in your findings on how to mod it for further improvements!
 
virtualrain said:
Thanks. Any pointers to data on the peformance with or without the alphacool res attachment?
Click to expand...

Alphacool Res Attachment will decrease performance reported by users
 
virtualrain said:
Did you mean to say "outlet channel" here? I mean with the Alphacool, no one uses the side inlet right but you must use the side outlet? Am I confused?

EDIT: I think you are referring to the inlet as per the mod described here?
http://forums.bit-tech.net/showthread.php?t=85428

At any rate, I'm interested in your findings on how to mod it for further improvements!
Click to expand...
No, no... I meant exactly what I said. See image below:
ill_19.jpg


As you can see, the inlet channel is about the same size as in the stock Delphi top--you're just eliminating the 90-degree bend at the inlet by using the top barb position. Widening that inlet channel to between 9 and 10mm will significantly increase flow. Modifying the outlet channel is very much unnecessary (remember, this is a pressure pump, not a circulation pump. You need a smaller outlet channel to help maintain pressure in the impeller housing).
 
So the inlet when using one of these tops is on the top? I wasn't aware of that.

Looking forward to seeing your prototype, Petra. Oh, and I must say, I'm enjoying the acetal fillport and gel pads - fine products.
 
Petra said:
As you can see, the inlet channel is about the same size as in the stock Delphi top--you're just eliminating the 90-degree bend at the inlet by using the top barb position. Widening that inlet channel to between 9 and 10mm will significantly increase flow. Modifying the outlet channel is very much unnecessary (remember, this is a pressure pump, not a circulation pump. You need a smaller outlet channel to help maintain pressure in the impeller housing).
Click to expand...

Sorry, my bad. I understand now.

In reviewing the reference StormShadow supplied over on XS I came across this...

MaGiX said:
I started with drilling/filing the top hole up from 7 mm to 9 mm. Got an increase in both flow (0,5 L/m) from 9,5 L/m to 10,0 L/m, and an increase in the pressure (+8 mbar.) going from 318 mbar to 326 mbar.

Not much, but some increase after all.

Then I bored the top up to 11 mm, and got pretty much the same result as with 9 mm (and yes, the ID of the fitting followed up, using 16 mm fittings.) That made me conclude, that drilling up to much more than 10 mm is useless, there is NO gain to se after that.
Click to expand...

Full thread here... http://www.xtremesystems.org/forums/showthread.php?t=108225

This is good stuff. This pump really is fantastic.

Before I knew better, I purchased the Ultra with the included reservoir... I'm still waiting for it to arrive. It looks like I'm going to have to ditch it to get max performance. Too bad.

What else do you have planned Petra?
 
Which is more important? Pressure or flowrate? No plans to change pumps anytime soon...but I'm bad about redoing cooling loops on a whim.
 
Both are really equally important. Why? Well, you obviously want the system flow rate to be as high as possible. You need a pump that can overcome the restriction of your components to flow X liters per minute. If you can calculate head loss due to your components, you can pinpoint, quite precisely, the theoretical system flowrate given a certain pump. In any case, you need a pump that can overcome the restrictions while pushing as much fluid as possible.

We've kind of settled on a few niche pumps based on a few different factors. We absolutely want a DC motor, because this significantly reduces the heat that must be dissipated via the coolant and it eases installation. We absolutely want small and quiet, but most of all, we want a good flow rate/head curve. We want great flow rates given great restriction because high performing components really have to be restrictive, but that's an entirely different subject.

You can't always have your cake and eat it too, but concerning the DDC, we pretty much can. A fantastic pump.
 
ok so based off of what you said what would be better
two dcc 1+ pumps w/ the new dual top
two dcc 1+ pumps with the 1/2 alphacool top in series
or
two mcp655 in series

im still trying to grasp the advantages of one over the other but i think i pretty much have it down after this question gets answered.
if the amount of blocks is important theres only one being used for this particular example. would that be overkill or would there be an actual benefit two pumps for one block?
 
dasilva333 said:
ok so based off of what you said what would be better
two dcc 1+ pumps w/ the new dual top
two dcc 1+ pumps with the 1/2 alphacool top in series
or
two mcp655 in series

im still trying to grasp the advantages of one over the other but i think i pretty much have it down after this question gets answered.
if the amount of blocks is important theres only one being used for this particular example. would that be overkill or would there be an actual benefit two pumps for one block?
Click to expand...

I don't know what kind of loop you are talking about but one DDC 1+ with alphacool top will likely be plenty. I think people here have a tendancy to overengineer things well past the point of diminishing returns. If you must run dual, I would still choose DDC over MCP655 due to the noise and heat advantages alone.
 
lol your prolly right virtualright, sometimes people get carried away so your saying that a ddc 1+ with the aqua cool top should be plenty for a loop with only one block, say the storm?
 
dasilva333 said:
lol your prolly right virtualright, sometimes people get carried away so your saying that a ddc 1+ with the aqua cool top should be plenty for a loop with only one block, say the storm?
Click to expand...

For one block... absolutely! Most people run multiple blocks with a single pump such as that and have fantastic results.
 
dasilva333 said:
lol your prolly right virtualright, sometimes people get carried away so your saying that a ddc 1+ with the aqua cool top should be plenty for a loop with only one block, say the storm?
Click to expand...

Depends you can get a DDC and TDX really cheap and being the only block in your system even the D5 is overkill.

What are the heat advantages of the DDC over the D5? I can't hear my D5, so the DDC must be damn quiet.
 
Justintoxicated said:
Depends you can get a DDC and TDX really cheap and being the only block in your system even the D5 is overkill.

What are the heat advantages of the DDC over the D5? I can't hear my D5, so the DDC must be damn quiet.
Click to expand...

I can't comment on noise, but the concensus seems to be that the DDC is quieter. Also, it draws less power, has less heat dump, is smaller, and has its fittings situated for more versatile placement options.

Wow. I sound like a real DDC fan-boi*. I'm not - really. But the DDC seems to be the new king of the hill for WC versatility.

*That seems like an odd word to ban. I had to edit in a hyphen just to get it to display! I'll try again: !!!!!!. Nope.
 
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