Plumbing Airbag Suspension question

[darren irvine]

Can anybody help me decide which way I should plumb the air lines to my airbags. I have been told to run each bag independently with its own valve and guage. I like the idea of teeing the front bags together as well as the rear bags. I want the front to air up off of one switch as well as the rear. I am not into the side to side thing. So, what are the pros and cons of running the bags independently?

[RunninLo]

see this thread:
http://67-72chevytrucks.com/vboard/s...66#post2410966

"tee"ing the bags on a common F-B set-up rides very poorly even with upgraded sway bar as air transfer from side to side induces a TON of body roll.
I used to prefer an 8 valve FBSS set-up with two vehicle mounted switches for FB action and then a 10-switch box wired to a 7-way trailer connector so I can plug it in and do FBSS for shows or criusing.

Right now I'm converting one of my old 6 valve set-ups that was indy front and "tee'd" rear to the 6 valve set-up that Kontrol Freaks outlines in the referenced post and using the same set-up in a new build. On paper it seems like the perfect solution and if it works well on these two the it is how I'll set-up my '72 burb.

Josh

[Kontrol Phreaks]

Yeah .. Werd ..

[jlaird]

oh man, I missed that 6 valve setup. Nice idea. I may try that. So with that setup, you cant dump each corner independently, correct? Not something that I foresee wanting anyway so this may be perfect.

[RunninLo]

Originally Posted by jlaird

oh man, I missed that 6 valve setup. Nice idea. I may try that. So with that setup, you cant dump each corner independently, correct? Not something that I foresee wanting anyway so this may be perfect.

it won't dump indy but it has a sort of leveling effect as it dumps and you can fine tune each wheel by adding pressure. Having finished switching over a minitruck today I gotta say I likey! before that sucker would slam to the ground now it's really quite gentle.

Josh

[jlaird]

hmmm, I think I may try the 6 valve setup.

I've got 3/8" valves, no airline yet. If I run 8 valves, do you think it will dump hard?

[IvelDesigns]

Originally Posted by jlaird

hmmm, I think I may try the 6 valve setup.

I've got 3/8" valves, no airline yet. If I run 8 valves, do you think it will dump hard?

with my 8 valve, 3/8" valve with 3/8" line, i don't think it dumps to fast. i'm using the SS RE7 bags with a single 3/8" opening. it's definately quick, but not so much that i worry about damage or noise.

[RunninLo]

i've used a few different methods to slow the dump speed. Those sintered bronze screens reduce airflow a bit and one of my friends has ball valves on his dumps to slow them down.
So far though the cleanest result yet is the 4L2D 6 valve. if you have the time you can always try a few set-ups and see which you prefer.
Josh

[7T7]

I know folks will probably think I'm full of poop, but I have done many 4 valve set ups and only a few needed to be switched to 8 valve independent. (to me a fairly simple addition)
In fact two trucks of mine have been on the road for over10 years and only have 4 valves. The only change on these trucks was a switch from Firestone to Slam Specialty bags. They ride and handle quit well and I have no planes to ever change to a 8 valve system on those trucks. But don't get me wrong....I'm not saying an 8 valve system is not desirable, it's just not necessary in all cases.

[N2TRUX]

Frank you have found the magic formula. I don't know if it's the Slam bags or what, but 73-87 trucks are terrible about air transfer if you don't isolate the front corners. The rear isn't as bad, but the front sucks even with a sway bar.

[RunninLo]

Originally Posted by N2TRUX

Frank you have found the magic formula. I don't know if it's the Slam bags or what, but 73-87 trucks are terrible about air transfer if you don't isolate the front corners. The rear isn't as bad, but the front sucks even with a sway bar.

I gotta agree, my guinea pig is a friends 88 Nissan Std cab 'vert. even with the modified front sway bar and a custom rear sway bar the FB only with 4 valves had very bad roll with that light of a cab. I then went to a T'd front 6 valve that solved that problem but had a few new inconveiniences. Just converted to 4L2D 6 valve and it's the gnat's a$$.
Josh.
ps here's the test mule I know it's not 67-72 or even a chevy but I was a poor kid once and mini's were all I could afford to be into: