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Airbags - install single or individual schrader valves?

Move Over

By Move Over
in Modifications & Accessories

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pronstar Enthusiast

pronstar

Posted
Posted
 
It just doesn't happen that way.  That's not how airbags work.
 
First, if you've ever filled one or let the air out of one, you know with the line sizes commonly used in these kits it takes a long time.  The pressure will equalize eventually, but it will take a very long corner--skidpad like--(or as I mentioned, slowly crawling over rocks or uneven terrain offroad if you stop for a while) for the pressures to equalize.  In dynamic maneuvers, it's a non-issue, there will be no measurable difference.
 
Even ignoring that and assuming for a minute the pressures would equalize instantaneously, don't take my word for it, look at the data for yourself:
 
Goodyear2B6-535Charts.jpg
 
 
That's the actual data chart for the bags in the Airlift 5000 system, some of the most commonly used on these trucks.  If you compare the graph on the left to the graph on the lower right, you can see how the bags act in each scenario.  With them connected so the pressure equalizes they'll act like the chart on the left in pure roll.  You can see their spring rate is much more linear than on the right, but it's still just a spring rate. 
 
If the bags are at 6" static height and under roll the outside is compressed 1" its load will increase by a certain amount depending upon the pressure at which it started.  And the one on the inside, which is extended by 1" decrease its load by a similar amount.  Just like your leaf springs or any other spring.  They will act no differently than an added set of springs.  They will add roll stiffness, not subtract from it.
 
Conversely, if plumbed separately, a very similar result occurs, just bigger as the outside bag gets into more of its progressive range so its load increase will be higher and the pressure the inside bag will be reduced a little so its load drop will be bigger.  The result is similar--they add roll stiffness, just more of it.
 
So no, they will not "compound the lean" in either scenario.  Both methods will add roll stiffness, reducing total roll, adding stability.  One just more than the other.  It's like comparing a large swaybar with a smaller one.  Just because the large one adds more roll stiffness, that does not mean the smaller one actually makes things worse and increase the roll.  It doesn't.
 
And again, that's assuming you're circling a skidpad or the like.  For dynamic handling and most real-world corners, the above is largely moot as there's not enough time to exchange the air between bags for people to even notice a difference in handling between the two setups.
 



Or we can look to what Airlift recommends:
https://www.airliftcompany.com/workshop/single-path-vs-dual-path/

b93498cad46121f2b54bce97e2b61ff0.jpg



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pronstar Enthusiast

pronstar

Posted
Posted
Gee, thanks.  They recommended exactly the same thing I did in my first post.  What they didn't do is agree with your contention that plumbing them together is "dangerous" in any way.  Because it's not.

 

Golly, you’re welcome [emoji106]

 

They literally state “dangerous travel” verbatim but I don’t read to good.

 

 

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Jon A Senior Enthusiast

Jon A

Posted
Posted

They say hauling a camper is dangerous.  Not that their airbags are.  It's quite clear.  They say the dual path is better for that application, just as I did.  Nowhere do they say that the single path is dangerous in any way.  That's something you made up or got from somebody who did.  Because it's not true.

Nitrousbird Enthusiast

Nitrousbird

Posted
Posted
7 hours ago, Jon A said:

They say hauling a camper is dangerous.  Not that their airbags are.  It's quite clear.  They say the dual path is better for that application, just as I did.  Nowhere do they say that the single path is dangerous in any way.  That's something you made up or got from somebody who did.  Because it's not true.

All the evidence and logic in the world will never change this guy's mind.  I mean, it sure must be dangerous - GM sold likely a million+ trucks/SUV's with a single path airbag system.  That system, though very prone to breaking, isn't dangerous at all.  If it were, there would be class action lawsuits over the last decade regarding it.  But let's not muddy the waters with facts...

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