Valves and Line

[kevncar]

Looking for advise on what size valves and line to run. I want the system to be quick, but not uncontrollable. I noticed SD sells 3/8&1/2 " valve kits, I assume the 1/2" would be th fill valve? Should I do something like this vs just running all 3/8? What about line size?

Thanks

[Frizzle Fry]

I have all 1/2" and I can tell you it's too damn fast! I necked a section of the rear lines down to 3/8" and it's much better. I'm gonna do the same on the front. I also installed needle valves on the vent ports to adjust dump speed.

[kevncar]

too fast up and down, or just dumping?
thanks

[cajundragger]

my bare frame with the engine and trans will hop the front 2" with 3/8 valves and line at 100psi.

With the body it slows a little but still is quick, and its only 100psi. I will run double this pressure when my comps on the truck pressurize the tanks.

I suggest 3/8 valves and line, or 3/8 valves and 1/2 line.

1/2 is just too damn fast.

[pharcydekm]

I run 3/8" spool valves with 3/8" line at 120-140 psi. It is plenty fast!

[cajundragger]

yeah and a FYI

diaphram valves are faster than spool...

[edflores]

i have 5/8 line with 1/2 fills and 3/8 dumps. fills arent fast enough and dumps are wicked fast so i put 1/8 reducers on. all at 200 psi. but my valves are in the bed.

[itsmike2k]

If you have the valves closer to the bags does that increase speed on fill?

[Frizzle Fry]

Originally Posted by itsmike2k

If you have the valves closer to the bags does that increase speed on fill?

Negligible

[jimmydean]

I ran all 1/2" valves and line only to learn it was WAY too fast. Fill wasn't bad in the front, but it was too fast in he back. The dump was all or nothing fast, you couldn't set ride height at all.

I would say all 3/8" line and valves. You could do 1/2" line, but the smaller line would be easier to run.

[itsmike2k]

Does your bags have 1/2" ports too? Mine have 1/4"npt ports but i ran 1/2" tube to 1/4"npt PTC fittings. Wonder how much that will slow down the fill?

[Shane]

your system is only going to flow as fast as the smallest orifice in the system ... it's called the Cv (C sub V).

[itsmike2k]

Is that a constant? Like if you have 10' 1/2" line with a 1/4" orfice is the flow the same as a 10' 1/4" line?

[Shane]

1/4" is 1/4" ... you can only push so much thru a given size orifice at a specific & constant pressure.

[itsmike2k]

so there is no atvantage at all to run 1/2" lines valves and fittings if your bags have 1/4" npt opening? I thought maybe since there was only 4 small points being 1/4 it would be better the having the whole system 1/4". Guess it doesnt matter since i already have all my stuff, just wondering..

[Shane]

you aren't going to get a 1/4" bag to flow like a 1/2" port bag ... regardless the size of the supply line

[BigSky71]

I am running 1/2 valves and 3/8 line. I like the fill, but had to restrict the dump to about a 1/4" hole. My ART ECU doesn't like the fill speed though... the valves run right by the preferred settings.

[itsmike2k]

What bags are you running BigSky?