couldnt you get an electronic speed control? that would probably work...

What do you mean? Like an electronic speed controlled pump? Or and an electronic speed control FOR the pump?

Negativity is the leader of all failure


Your not a dumbass...But that was pretty funny ;)

Leadership is also about avoiding pointless venues, because they're impractical (hence people don't want a leader who will wste everyone's time).

I'm glad to see that you thought it was funny, but just like your suggestion, very few people share your point of view.

I wrote that this is a bad thread because you are not getting very good information (some good, some bad). I really do hope that you will find a way to drop the voltage on your pump, and like I said, your idea does have some merit.

You could probably take the circuit of a dimmer, and adapt that design for a higher power rating. It depends on how much you know about electronics.

The curcuitry involved in an oscillating fan could work for your circuit. The concept is the same as my diode idea.

The electronic speed control won't work, if it's the type used in RC cars. Electronic speed controllers like that (which cost around $50 btw) are designed for DC circuits. So Cyco-Dude, you'll have to clarify what you meant.

You could just use a transformer: it will convert 120 VAC to XX VAC, straight out, but again, you won't have any flexibility. You could get a transformer with a multi-tap, which will give you a range of voltages, and switch from one to the other. Prepare for a big expense though.

Why don't you give us the specs for that pump (manuf., model, power, etc...). We can look it up and maybe we can help you a bit more.

And by the way, the reason you're taking a lot of flack on your idea, is simply because too many people have tried using an increasingly powerfull pump. So when you suggested using a 900 gph (regardless of undervolting), you attracted some attention.

In a previous thread, some guy published a study suggesting that a min. 30 gph flow (not pump rating), would provide most cooling, and as his graph shows, anything less is exponentially inneficient, and anything more is exponentially irrelevant. This of course is still open for debate, but the number is out there.

If you're really getting 1-2 psi in your system, then that's great. Anything more than 5 psi start becoming inefficient (as it increases flow resistance significantly). Now, how do you know that you have 1-2 psi?

get a speed control for AC circuits; they do exist. for example, you can get one for the single-speed dremel rotary tools.

I think that will work CD, as long as it can handle the current!!!

Thniking some more... I don't think the transformer idea will work, simply because you won't be able to find the part to convert 120VAC to say, 100VAC or even 60 VAC. It's out there, but it's not a very common part.

You've hinted that you intend to use that 900 gph pump at full power:
You've been warned:
Yet you are persistant (that part is good)

Dude...Get a life.

Seriously man, all that space crap. I dont care.

And Ya I guess Ill quote myself saying its industrial, but If industrial pumps are 45 then I guess it is. So who cares if its freakin industrial or not, its a strong ass pump.

And no I never indicated im using the pump at full power, How many times do I need to say it.



This thread it probally going to get banned, but I learned alot, Ive learned that its easier to just use a small pump, but kinda fun to phock around with big ones. And alot of other stuff I dont want to go into.

But your just a pain in the ass man, You succed at being very smart with your nasa crap that is not needed, just cause I said We went to the moon.

What are you trying to prove? That your probally smarter then EVERYONE here? or me? Which you most likely are when dealing with computers.

So stop posting in this thread, your ruining it trying to show off with your vast knowledge of nasa.

Care tho? Nope.

Why don't you look into Cal pumps. They have a few models that have an adjuster for the flow rate built into the pump itself.
You could just have a bypass tube flow back to a resevoir with a lever valve on it. That would allow you to vary it. The tubing up to and including the bypass could be 1" hose and at the bypass reduce down to 1/2" to continue your loop to the block and rad, this might keep your pump from overheating.

Hmm sounds like a great pump.

I was thinking the SAME thing with the bypass valve!

It would be some work going from 1'' to 1/2''

Maybe Ill try it out sometime.

You may have to reduce using two couplers but even that is an easy task.

Ya Ill have to hit up Home Cheapo, They have a crapy selection for plumbing

You know what? You should go ahead and get the big pump. In fact, why not try out a marine bilge pump? Whatever you do, just make sure to grease all of your hose couplings/barbs. Oh, and don't forget to remove any hose clamps you might have, as these will only restrict your flow rate.

:D :dome:

Help, the sarcasm is overflowing into... this... post. Now where's that waterpump to bail me out:D

I already did that.

(Thanks ECUPirate, you're my hero...)

Cieprus: I have tried to help you in your effort: I've suggested a diode circuit, and a transformer. I've confirmed that your oscillating fan controller was a good idea. I did however point out the difficulties that you are facing, but obviously you knew them too well.

Good Luck.

hehe.. do what you want man. just let us know what happens.

Well ECU.

Ive seen a 600 GPH @ 12.

Do you think thats ALOT better?

I guess I could downvolt it to 7v.

And have it pump at 350 GPH (Wrong number? Crapy math skillz :))

Im going to work on Using a dimmer on the 950 beast, Ill let you know how it works, and the pumps temps!

Here's a thought... I'd like some feedback.

Say you take a 900GPH pump and some how run it at say, 400GPH (w/ zero load/head), and you pit it against a true 400GPH pump. I'm willing to bet that that the true 400GPH will be able to generate more pressure/head, and it will do it more efficiently and last longer.
A 24v fan rated at 120 CFM running @ 12v won't perform as well as a 12v fan rated at 60CFM. It will be louder due to the pitch of the blades, and it most likely won't develop as much pressure because it is spinning about half as fast as it was designed to spin. Personally, I have three 24v fans. Two of them are Papst 120's, 4314 fans. I got them for less than $5 each, so that was justification enough for me. I also have a 24v PSU I'm trying to rig up, but that's another story. :)

Ive gotta work with what ive got man.

So if I downvolt that 600 GPH Marine pump...Do you thing it will have a problem?

I don't know man. I've never heard of anyone downvolting a pump... ever. But hey, maybe you can. If you already have the stuff, go for it. But don't buy a 600GPH pump so that you can downvolt it. I realize that perhaps you want the option of cranking up the flow rate, but I've never seen a WC setup that required that much flow, unless it involved a 6' bong cooler and 12 heatercores. :)

Guys, keep the talk polite. I see some people on both sides being funny but rude at the same time, and that is a dangerous line to walk. We want to keep the signal to noise ratio high, and the forums need to be friendly to everyone who is open to learning.

No flaming!

What kind of current does your pump draw? If it is less than 3A then you should be able to run it on a really inexpensive Variac (check ebay). For more powerful pumps the VariAcs get expensive. I am thinking about doing exactly the same thing to a 500GPH little GIant I have for testing purposes. This works more nicely than a ball valve because you aren't fumping a ton of heat into the water when you throttle it back. I am not sure a simple dimmer switch is going to be a good long term solution for your pump though...

I've down volted 12v pumps before (7v and 5 v), it won't hurt them, but won't stop them dying quickly either (re, DC pumps having around 3month life span)

I dunno about that man..

I own a 44cfm 60mm delta. at 7v it moves more air than my ys-tech 27cfm's and it is much quieter.