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Just run 1/2" line up to the front then Y it off to 3/8"!! ;)
 

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With 2 3/8" line you will also get more pressure because there is less pressure drop in a 3/8" line. if you run a 1/2" up to 2 3/8" the advantage will be lost because the dual 3/8" line will only be able to flow to the limit of the 1/2".
 

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WTF, the smaller the hose, the more pressure drop..

are you confused, or just stupid?

3/8 hose has an area of 0.1104", and 1/2" hose has an area of 0.196"

so technically, 2 3/8's hoses will flow more fluid than 1 1/2" hose, with less of a pressure loss to boot.
 

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I sure hope you are not calling me stupid.

If you are commenting on my post i think you are the one confused!

I never said you would lose pressure by using the 3/8" hose.
 

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Originally posted by westrides@Oct 22 2003, 10:16 PM
you guys have me all confused now. so which is better????
you build more pressure using hoses like #6's

you get more volume by using hoses like #8's

like , #5, #6 pumps have more pressure, but pumps #7, #9's and up, put out more volume.

you need to match your setup.


your most likely not going to run a #5/#6 pump with number #8 hoses, all the pressure of the #5 will be lost because you are pumping them through a large hose.

same thing with a #7/#9 pumps, you don't want to run them through a #6 hose because the flow will be restricted by the small hose. and you will lose flow/volume to fill.

you need to tweak your fittings and hoses on your set-up.

i hopped on old fenner #6's with #6 hoses.


if you have #7 or #9 run #8 hoses.

pm homies like hydrota or vegashopper, these guys are active professionals.

:),

c



Last edited by Cruz_Campos at Oct 23 2003, 02:19 AM
 

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The inside surface of the hose acts as the resistor as well as the fluid itself. The pressure produced is what the pump produces to shove the fluid through the hose. It's the acting pressure to the cylinder itself that matters. Remember, the diameter of the stroke is about 1 1/4" ID The cylinder is using dynamic pressure, meaning the pressure of the fluid will be less in the cylinder than what is moving through the hoses. Even though the fliud spits into the cylinder at a high pressure, once the stroke starts to move, then pressure is less at the head of the stroke.

Two #6 hoses allow greater flow than one #8

It never hurt to read a hydraulic book or two.
 

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Originally posted by Cruz_Campos+Oct 23 2003, 02:17 AM--></span><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td>QUOTE (Cruz_Campos @ Oct 23 2003, 02:17 AM)</td></tr><tr><td id='QUOTE'><!--QuoteBegin--westrides@Oct 22 2003, 10:16 PM
you guys have me all confused now. so which is better????
you build more pressure using hoses like #6's

you get more volume by using hoses like #8's

like , #5, #6 pumps have more pressure, but pumps #7, #9's and up, put out more volume.

you need to match your setup.


your most likely not going to run a #5/#6 pump with number #8 hoses, all the pressure of the #5 will be lost because you are pumping them through a large hose.

same thing with a #7/#9 pumps, you don't want to run them through a #6 hose because the flow will be restricted by the small hose. and you will lose flow/volume to fill.

you need to tweak your fittings and hoses on your set-up.

i hopped on old fenner #6's with #6 hoses.


if you have #7 or #9 run #8 hoses.

pm homies like hydrota or vegashopper, these guys are active professionals.

:),

c[/b][/quote]


Why is it that the larger gear/number put out less pressure than a smaller gear/number?

It is true, but why? What is the theory of it?



Just asking. :)

I'm still waiting for an answer, and I have noted about 400 hits to the question, here on LIL and SD http://www.squaredump.com/forum/viewtopic.php?t=92
 

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Originally posted by Cruz_Campos@Oct 23 2003, 04:17 PM
you build more pressure using hoses like #6's

you get more volume by using hoses like #8's

this misconception keeps appearing here...............................

people are confused when they see that "a smaller hose will increase your pressure"...................in a way this is true BUT not in a good way!
in general a pump will have to push harder to move oil along a smaller hose. This can increase the pressure at the head but this does not mean your system will be better.
what you want is the optimum flow and pressure at the cylinder, this means the correct size ports/hose/fittings/valves all the way.
bigger is not always better.
smaller is not always worse.

the topic had been gone over again and again here in the past........if you think running a smaller hose to get a higher pressure is better take the principal to the limit, go small enough that there is no hole in the hose and you will have the highest pressure the head can possibly produce.............. but it wont do a lot for your ride. A silly extreme i know, but you get the point. :)




:) :)
 

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You know, I once read in a text book that GM used a smaller tubing to the brake cylinders for a higher pressure. This made no sense to me. The only way I would think this makes any sense is that as the fluid flow exits the tubing, into the cylinder there will be a blast of fluid.

This got me to thinking, in a small cylinder compared to a rather large cylinder, this might make sense. I guess it would be that the spitting or blast of fluid that moves extremely fast under pressure, hitting into the piston (thinking very small cylinder now) may force the piston to move fast at the very instants the fluid hits it.

Something like a bullet hitting something and knocking it over.

Hmm ... maybe we should ask a competent hydraulic engineer.
 

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I read some were that if you want to see an inprovement when you wire your pumps at more than 48v you should move up to #8 hose....go with what ever is easy....if you allready have 2 #6 hose use them
 

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Originally posted by air280+Oct 23 2003, 04:41 AM--></span><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td>QUOTE (air280 @ Oct 23 2003, 04:41 AM)</td></tr><tr><td id='QUOTE'><!--QuoteBegin--Cruz_Campos@Oct 23 2003, 04:17 PM
you build more pressure using hoses like #6's

you get more volume by using hoses like #8's

this misconception keeps appearing here...............................

people are confused when they see that "a smaller hose will increase your pressure"...................in a way this is true BUT not in a good way!
in general a pump will have to push harder to move oil along a smaller hose. This can increase the pressure at the head but this does not mean your system will be better.
what you want is the optimum flow and pressure at the cylinder, this means the correct size ports/hose/fittings/valves all the way.
bigger is not always better.
smaller is not always worse.

the topic had been gone over again and again here in the past........if you think running a smaller hose to get a higher pressure is better take the principal to the limit, go small enough that there is no hole in the hose and you will have the highest pressure the head can possibly produce.............. but it wont do a lot for your ride. A silly extreme i know, but you get the point. :)




:) :)[/b][/quote]
true my friend, but i was talking about a #5, #6 pump.

use this #5/#6 pump number with a #8 hose and you loose pressure.

for #5/#6 i've alwasy used #6, on anything bigger than #9 i definitely go to #8.


:),

cc



Last edited by Cruz_Campos at Oct 23 2003, 08:40 PM
 

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also true.........the brake thing and with smaller heads, but its not the pressure that improves things its the response.............having smaller bore hoses means there is less fluid to move and repressurize each operation, so the ultimate system pressure can b reach sooner.

the pressure that matters is that produced [in our case here] by lifting the car, any "extra" pressure created by small hose/wrong fittings/too many ebows is not good pressure, it is just pressure that makes the system work harder for nothing.

the most efficient flow rate for a hydro circuit is 7 - 15 ft/sec on the pressure side, any lower [big pipe] and the response will drop, any higher [small pipe] and the parasitic pressures increase.
The flow rate is a product of pressure and flow.
The problem with any figures you can find is that they will have been produced for industrial situations, where "normal" operating pressures are around 3000psi and the cuircuit is a static constsant thing............our circuits run at silly pressures, and flow rates vary by huge amounts as we lift and dump, and ask fluid to lift/support the ride and then to compress a fcuk-off big spring.
So, going back to the original question, it is wrong to assume bigger is better etc, but text books are of limited value to us here. The best way to decide is to listen to someone who has done it and found out from experience, then to have a go and see what works with your system. :) :)
 

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Originally posted by air280@Oct 24 2003, 01:02 AM
also true.........the brake thing and with smaller heads, but its not the pressure that improves things its the response.............having smaller bore hoses means there is less fluid to move and repressurize each operation, so the ultimate system pressure can b reach sooner.

the pressure that matters is that produced [in our case here] by lifting the car, any "extra" pressure created by small hose/wrong fittings/too many ebows is not good pressure, it is just pressure that makes the system work harder for nothing.

the most efficient flow rate for a hydro circuit is 7 - 15 ft/sec on the pressure side, any lower [big pipe] and the response will drop, any higher [small pipe] and the parasitic pressures increase.
The flow rate is a product of pressure and flow.
The problem with any figures you can find is that they will have been produced for industrial situations, where "normal" operating pressures are around 3000psi and the cuircuit is a static constsant thing............our circuits run at silly pressures, and flow rates vary by huge amounts as we lift and dump, and ask fluid to lift/support the ride and then to compress a fcuk-off big spring.
So, going back to the original question, it is wrong to assume bigger is better etc, but text books are of limited value to us here. The best way to decide is to listen to someone who has done it and found out from experience, then to have a go and see what works with your system. :) :)
agreed homie


#5/#6 use #6 hoses, #9 and up #8 with larger fittings.

if you have pumps like a #9 or higher with more flow, you don't wont to run a #6 hose, you defeat the purpose.

vice versa with a #5/#6 with a # 8 hose. homies may not know and understand physics and formulas on psi vs. volume. but they now that the basic principle of what i posted is true.



:thumbsup:,

cc
 
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