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Question for people using watercooling.

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Well if you want to just do testing, then what I use are 2 x Laing D4's in series hooked up to a variable voltage power supply. I can run them at anything from stall voltage (4.8v) all the way up to 16v, which is the limit of my PSU. At 4.8v, together they're about as powerful as the Eheim 1046 (very weak - ~1.5PSI max @ dead head). At 16v, together they're about as powerful as the US spec Iwaki MD40-RZ (very strong - ~20PSI max @ dead head).

Makes it fairly easy to set your flow rate just by turning the voltage knob on the PSU.
 
slater3333uk said:
Yeh sounds good. I think an interesting thing to test would be how the deapth of the shroud effects matters and also if push or pull is better cous i think that matter could do with settling

Dual vs Single pass would be very interesting

the shroud height question is one that I am fairly curious about as I have built quite a few of them. When you are trying to cram all of the H2O gear into a case, a thinner shroud would have obvious benefits provided there wasn't a substantial performance hit. Thus far, with fans in pull as opposed to push, I haven't been able to find much of a difference between shorter and taller shrouds (at least as applied to '77 bonneville cores within a certain range).

I have one that is about 1.5", another right at 1" and one that is about 3/4" -- with the same fans on all three, the temps are virtually identical. I haven't tested that with the fans pushing on all three as opposed to pulling yet. I suppose I need to add one with almost no standoff (1/4") and another with a much taller standoff (like 4") to determine if there is any difference at all related to the shroud's top plate height. Adding a divider plate seems to improve performance regardless of height.

On my '77 b'ville cores, with the same shroud height, switching between push and pull didn't produce any noticable temp drop but the pull method was a bit quieter. Of course, that might be due to the fans in part - I was running dual SanAce 120mm fans that are rated for 103CFM each so 206CFM for the pair if you go by the specs. I wonder if it makes more of a difference with lower CFM fans?? dammit, there is something else to test. ;)

I am also curious about the shape of the shroud - it seems to be fairly well accepted that a venturi shape is better than a flat sided box under the theory that it helps smooth airflow thru the fins in the core but how much of a difference does it really make? The venturi style shroud is more of a pain to make as you have to figure in all the angles and then make the cuts correctly where a flat-sided box is a no-brainer to make in comparison. IMO, the venturi gets some points in the aesthetics department, though.

Cathar said:
Well if you want to just do testing, then what I use are 2 x Laing D4's in series hooked up to a variable voltage power supply. I can run them at anything from stall voltage (4.8v) all the way up to 16v, which is the limit of my PSU. At 4.8v, together they're about as powerful as the Eheim 1046 (very weak - ~1.5PSI max @ dead head). At 16v, together they're about as powerful as the US spec Iwaki MD40-RZ (very strong - ~20PSI max @ dead head).

Makes it fairly easy to set your flow rate just by turning the voltage knob on the PSU.
that's a damn good plan - I have a Lambda Wattbox with 4 adjustable rails on it somewhere...hmmm...I might have to order a mag3 and then a pair of the D4's to cover everything else. thanks for the insight, Cathar. :)
 
slater3333uk said:
What do you mean by 'Adding a divider plate'?? some kind of baffle within the shroud?
Sounds like a plate between the two 120mm fans so their flows don't interact.
 
SureFoot said:
Sounds like a plate between the two 120mm fans so their flows don't interact.

exactly. it divides the shroud compartment into an upper section and a lower section so each half of the core has a dedicated 120mm fan. I normally use a piece of 24gauge metal or 1/8" thick plexi for this depending on what the rest of the shroud is made from.
 
I just wanted to say something about pump alternatives. Ive been saying it a few times b4, but now i got off my *** and found a linky for it as well.

http://www.grundfos.com/web/grfosweb.nsf/Webopslag/54C886918BA128C4C1256D56003FA7C8

These are expensive if u buy em new, but not really the kind of thing that breaks down this decade, so either pay up or get a used one from a plummer.

I did.....

Oh also, they have 3 speed settings: much, more and a hell of a lot :)
Seriously, they (as far as i can tell) are pretty good. the one i have is called grundfos 25-40-180 (25-40 kv 180) if anyone is interested
 
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As long as you have something standard for the readers to compare to, like a mag3 the results should be fine. If you make an adjustable pump rig then you're gonna have to measure the flow rate and pressure for users to compare.

Think the following pumps are more widely available and purchased by new WCers than a Mag3.

Eheim 1048 - 158GPH - 4.9ft - 10 watts
Eheim 1250 - 317GPH - 6.6ft - 28 watts
Hydor L20 - 185GPH - 4.4ft - 14 watts
Hydor L30 - 320GPH - 6.4ft - 23 watts
Via Aqua 1300 - 370GPH - 5.7ft - 28 watts

You have to consider that most new people going into WCing don't have the money to get a Mag3 or MCP600. Most often, if they do have the money to buy a nice pump they will not bother with buying a heater core to mod and paint.

You basically have 2 targets, low budget and high performance. Low budget would use a cheapp pump and would spend the time to mod a core to get every penny worth. High performance guys/wc vets are more interested in what they could get and mod to get best performance sometimes regardless of the cost.

Ideally, you'd want a low end pump and high end pump to test with, but if that doesn't flow with ya, you can do the adjustable pump thing like Cathar. If you're doing this for personal curiosity rather than publication, then it's really up to you.
 
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