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The early stache
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Discussion Starter · #1 · (Edited)
I know there has been multiple threads on this but I want to show how I bagged my nbs. I tried to keep most of the info generic but I also threw in some nbs specific information. I have recieved multiple private messages asking for my build thread or general air bag questions. So here is my explination, opinions and how I did it. If you have any general air bag questions or nbs air bag questions feel free to ask me and I will update this thread to answer the question.

To start off I want to explain how an air bag system works. The heart of an air bag system is the air management. You have to have a way to compress the air and then store enough of it to fill the 4 seperate air bags that will support the truck. I use an engine driven compressor but some other people use 1 or more electric compressors. The compressors are turned on using a pressure switch. When the pressure drops in the air tanks to a certain level the pressure switch shorts and completes the electric circuit to turn the compressor on. I use 2-5 gallon tanks to store air which is plenty to lift the truck to ride height from the ground. The minimum pressure switch I would recomend would be a 150psi, and the maximum I would recomend is 200psi.

With the air stored in the tanks there has to be a way to transfer the air to the bags. Some people choose to control the front air bags together and back air bags together but I prefer to contol each bag separately. To control each bag separately you will need 8 valves. 4 of them will fill each bag and 4 will dump the air out of each bag. When I first bagged my truck I used an avs-9 switch box to control my 8 valves. It has 9 switches that can control each bag individually, the front, back, left, right, or all bags at once. Asside from 8 individual valves there are valve manifolds availible also. I have upgraded from 8-3/8" valves to 1 Accuair VU4 manifold. And instead of the avs-9 switchbox I upgraded to the Accuair E-level. For more info on Accuair click on my "Accuair Install" link in my signature.

Installing the front air bags is simple. All you need is the air bags and some cups to make the desired length between the lower control arm and the spring pirch. I also used a 2" drop spindle.

The back is way more complicated. There is an infinate number of ways to do the back so I will just explain the basics and go more into depth with what I have. No matter what you choose to to do you have to get rid of the leaf springs and the hangers that hold them to the frame. To control the axle you can use a 2, 3, or 4 link. I have what is considered a 6 link but it is basicaly a 4 link with extra attachments to attach the bags to the axle. You will also need a way to keep the axle from moving side to side (unless you use a tri-4 link or wishbone). I used a watts link but a panhard bar works also.

The frame will be in the way. I lay frame on a 30" tire (265/40/22) with a 6 3/4" notch. There is 1/4"-1/2" between my axle and frame notch.

Here is my air tanks installed where my spare tire was behind the axle.


This is a horrible picture because it was taken in the middle of my body drop so excuse the mess. I'm posting it so you can see my engine driven compressor mounted next to the alternator on the passenger side of the motor.


Here's the front. Pretty simple. Just an air bag with cups. I have mine bolted to the spring pirch and free floating on the bottom. Top cups are 5" and the bottoms are 1". The belltech spindles (pt#2508) are installed and the upper control arm is flipped over to help ball joint angle.



Here is the link to belltechs instalation guide for installing the 2" drop spindle. Most importantly in this link is directions and pictures for flipping the upper control arm. Basicly you remove the uca, press out ball joint, press the balljoint in the opposite side of the uca, and reinstall the uca with ball joint facing the same way as before(down). Go to step 3 in this link. http://www.kw-gmbh.de/kw_upload/Einbau/2508-888.pdf

This is a high tech, exaggerated rendering of what flipping the uca does for ball joint angle


Here's the back all setup with the kp 6-link, watts link and the air tanks installed.






Here is a picture of all the fittings I used. 1 set of these for each bag. They should be conected in the order that they are laid out in the picture.


Also here is a couple threads from when I did this
http://www.fullsizechevy.com/forums/general-discussion/street/269834-07-classic-project.html
http://www.fullsizechevy.com/forums/general-discussion/street/278513-07-classic-updates.html

I will continue to add info to this but this is atleast a start for now. If I left something out or you have questions please feel free to let me know.
 

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TROLL REVOLT of 2012
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2,474 Posts
hey numatk, how much did your set-up run you for?

thats a good write-up, it gave me a better idea of whats to come.
 

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TROLL REVOLT of 2012
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2,474 Posts
i was looking at the pictures, and the rear looks like a basic bolt on thing, unless theres other stuff you gotta weld besides the notch.
 

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The early stache
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2,503 Posts
Discussion Starter · #14 ·
hey numatk, how much did your set-up run you for?

thats a good write-up, it gave me a better idea of whats to come.
I tied to add it all up once but it's hard cause there's a lot of nickle and dime stuff. I spent somewhere around 4k - 4.5k. It can be done for about half that if you get the right parts and can fab stuff up. If you want the bolt on stuff it's gonna cost ya.
i was looking at the pictures, and the rear looks like a basic bolt on thing, unless theres other stuff you gotta weld besides the notch.
All the kp stuff was bolt on. Had to do a little fab work on the air tank mount, notch and to raise the gas tank. To bag it all I used was a grinder, sawzall, welder, and some basic hand tools.

Thanks for all the possitive coments. I didn't expect it. I was just going to save the link to give to people.
 

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The early stache
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2,503 Posts
Discussion Starter · #15 · (Edited)
nice. heres a noob question, how can you tell a 2 link 4 link 6 link and wishbone set up and other set ups apart?
What ever number it is is how many bars connect the axle to the frame. A wish bone has 3 links with 2 on the bottom for each side and 1 on top. but the top one is shaped like a wishbone and connects to the axle in 2 spots and to the frame in 1 spot. A triangulated four link has 4 just like a regular 4link but the top 2 are triangulated to keep the axle centered. a watts link or panhard bar are not needed on a wishbone or triangulated 4link. A wishbone setup is awesome because it can be designed to keep the stock gas tank location and it uses the least amount of parts so it is the cheapest.

azdragginsoon's wishbone




Kind of crazy to look at but here is whytry85's triangulated 4 link. lower bars on the outside of the frame and the upper bars are on the inside of the frame and traingulated to keep the axle centered. If you notice the bag possition it looks like a 3 to 1 ratio. That means that every inch the bag expands the axle wil move 3 inches. That makes the truck ride very soft. Probably too soft imo. He could have mounted the bag any where on that bar. moving the bag taward the axle would make the ride more stiff and moving the bag toward the engine would make it more soft. Usually 1/2 way on the bar is prefered, or closer to the axle.



I'll search pictures for each and edit this post
 

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The early stache
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2,503 Posts
Discussion Starter · #17 ·
Whats up bro, i was gonna ask you about the ride quality on your bagged truck. How well does it absorb bumps and riding through rough roads, compared to stock?
The KP kit rides soft IMO. It's a 2:1 leverage setup. so the weight on the bags is 2x that of the rear axle weight. Which is good because it gives 2x the lift of the bag. So for every inch the bag expands the axle moves 2 inches. It rides softer than stock. Same with the front. The ride quality is way better than stock as long as you get the correct part combonation up front. With any bagged vehicle it rides more stiff with every psi you add to the bag. So there is a sweet spot with psi. I like to ride as low as possible for the road conitions which makes my truck ride a little softer than I like. Shocks help with that. I need to get a stiffer set of shocks but I might wear out my current set first. Like I said, the kp kit is a 2to1 ratio, which can be set up with a tri4 or wishbone based on bag location.
 
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