Air bag suspension (3 Viewers)

[thelal]

Lacrusier,

I had thoughts of doing this a few years back, exactly as u described, but have not got around to it. I had some design ideas knocked up with an engineer.

However Scott and Heath had some good comments worth noting.

I'd be interested in where u go with this. Drop me a line.

 

[Radd Cruisers]

Seen pictures of his rig, no real feed back on how it works for him?

Oh, note that his rig is BJ60, no joke he turns those 53s with a turbo charged 3B diesel.

Doesn't Peter Straub up in Canada have air bags on his huge lifted FJ60? he'd be one to contact; check the 60/62 boards.

I know from Land Rover friends that airbags can fail at the most inopportune times--LR owners swap them out for regular coil springs. This includes the new versions that lift the Disco and/or LR3 higher or lower, as you are planning for. FWIW. Your system can't be any worse than what the Brits designed!

Dave

 

[Behemoth60]

Seen pictures of his rig, no real feed back on how it works for him?

Oh, note that his rig is BJ60, no joke he turns those 53s with a turbo charged 3B diesel.

Radd dragged me into this.

I would not think that air bags 'just to get over big rocks' is a good idea. Bags cannot really run 'empty', then inflate them when you need them. When they run empty, they get deformed as they move around, and this can cause premature wear. Just go 100% bags, or stick with coils and slide over the rocks you can't fit over like everyone else.

Bags definately work different than coils. Having them adjustable is nice, but relying on them to keep the truck level is a huge problem. A serious anti-sway bar is definately needed, something my rig doesn't have and suffers for as a result.

One of the nicest setups I've ever seen is on a custom buggy built by a guy here in Calgary. He put air regulators on each air bag, and used beefy anti-sway bars to keep it level. With the air regulators working, they keep even amounts of air pressure in each air bag, which results in even ground pressure under each wheel right up to the point where the limit straps come tight. Forced articulation! Works awesome. He can then adjust height by adjusting the regulators.

I used a rolling lobe style airbag, which tend to provide the most travel. Mine have 14" of travel. If I were to do it again, I would go with a bellows style bag mounted partway up the lower link. Then you can use a bag with a shorter travel, but still get lots of wheel travel. But that might be more work than just swapping out the coils on your truck.

Peter Straub

 

[Walking Eagle]

Ok, what bags are you using - as in make and model.

Are all of your bags run independently? I'd think if each is seperated, they should (should is a dangerous word of course) just be like seperate coil springs, unless your bags happen to have spring rate that is low compared to a comparable lift coil.

You could have a valve in a line between the two front or two rear bags, which when closed would make the bags work independently like springs, and when open, would equalize the pressure between the bags. When open, it'd be a handfull on the street I'd think.

That's one of the deals they warn about with even the helper bags that go inside your springs. If you run them into a T, you get more sway.

 

[alia176]

Ok dudes, air bag suspensions are a whole can of worms! I know it looks/sounds easy but it just ain't that easy. Bag inflation algorithm, shock valve selection, compressor capacity, pressure differential from front to back, manual/auto control, feedback systems, etc is very complex. Pressure control based systems don't do as well as height based controls. However, a computer is needed for height based control and that's another can of worms. You'll be seeing more and more of the height based systems in the market as technology improves.

Offroadonly does a good job with light weight Wranglers but our vehicles are all together different. Low riders that use air bags for making the cars go up/down has no interest in ride quality on or off road, let alone articulation, droop, stuffage, etc.

The original air suspension system from LRs worked great except their parts quality was sub par. The system was not bad with the exception of the "limp" home mode. Their limp home mode was driving home on bump stops! Offroadonly studied this system and improved on it by making the "limp" home mode much better.

Just some random thoughts....

 

[desertdude]

Dana - I Thought about this for my Tacoma Firestone airbags

 

[Walking Eagle]

Ok dudes, air bag suspensions are a whole can of worms! I know it looks/sounds easy but it just ain't that easy. Bag inflation algorithm,

Just some random thoughts....

You are way over thinking this. In the simplist set up, you put bags in place of the springs - don't link them each other or a compressor, and they work just like springs. Then, from there, you start to add with compressors, and valves, which is still pretty simple.

If you try to add self leveling, and stuff - ya, then it's going to get complicated. I don't think that's what we're talking about here - we're talking a pretty simple system - or at least I was