Air ride suspension questions

[uppster]

I bought a 71 Suburban that has a home made complete air ride suspension with front and back separate controls. I am having trouble adjusting it for a normal ride. 2nd is durability and reliability. When I complete the LS swap I will drive it everyday and on trips. I am contemplating removing it and going back to dropped spindles and coils. I know the basics, trucks have bags etc. But I would like to hear from actual users that have had them for a while. Thanks

[Ziegelsteinfaust]

I built one air ride kit for a kid I knew, but alot of details were based on his preferences.

You Burb should have 8" bags in the front, and probably 7" in the rear. Smaller bags, and the psi will be to high. This giving a stiff to horrible ride. If your using Slam Specialties style bags.

Air bags should be mounted at free standing height at ride height. So let's say your air bag on your work bench stands at 8" tall. That should be the installed ride height measurement. When I did the kids air ride system we made spacers so that he could dial in what he wanted.

You could have something as simple as to much lift in the bags vs there original set up. To it was just built wrong.

[Andy4639]

Originally Posted by uppster

I bought a 71 Suburban that has a home made complete air ride suspension with front and back separate controls. I am having trouble adjusting it for a normal ride. 2nd is durability and reliability. When I complete the LS swap I will drive it everyday and on trips. I am contemplating removing it and going back to dropped spindles and coils. I know the basics, trucks have bags etc. But I would like to hear from actual users that have had them for a while. Thanks

I bought a complete air system about 10 years ago. Thinking I would install it in my truck. I never could do it. My truck rode so nice with the set up I had I didn't want to mess it up. I drive mine on a daily bases also. I ended up selling it.
Air ride trucks are very cool to look at and see working. But practical I don't think so.

I now have helper air bags in all 4 springs and it rides even better now. I have a static drop of 3" in front and 4" out back. I used the lowered coil spring's and they where to soft, not anymore. I'm riding on air now and have the back up of a spring also.

[uppster]

thanks

[joedoh]

most air suspension problems are perceived problems from unrealistic expectations. what I mean by that is:

your ideal ride height is going to be your droop height + half travel. so if you have a bag with 6" of lift, and your droop height is 2" off the ground, your good ride height will be 5" off the ground. you can get a little more with the leverage of the front a arms, so a 6" bag will have 8" lift, and your ride height will be 6" off the ground. this is why shockwaves (shocks with airbags) look appealing but really only work on trucks with a desired 2" lowering when parked.

too many guys say ok, I want the truck to lay frame, or body, and because I have 8" of lift it will lift to 8". you can ride around at full lift but an airspring spring rate depends on pressure, and high pressure = poor ride.

you also need shocks that can travel that much. on an 8" travel spring you will want shocks that travel at least 10", giving you a little room to bottom out the spring without bending the shock mounts. they should also be gas charged shocks. I dont know if you have looked for shocks with this criteria but good ones with long travel (look at 4x4 trucks for donors) arent cheap.

set your bags up to be squished 100% at full droop. any extra space left in the bag is extra pressure. most times your droop height is set by things other than the frame, a balljoint will bind at a certain angle, or the lower arm hits the frame before the frame hits the ground. this may require you to trim (or add to) your spring cups to get this full squish at full droop.

as mentioned, this is not like bigs and littles tires, the big bags go up FRONT where the heavy stuff is, and smaller bags out BACK where almost nothing is. you might be tempted to use big bags all around but since spring rate is dependent on pressure, a big back out back will "lock up" (lift fully to suspension limit or bag limit) with low pressure, and mid height will be at even lower pressure, leading to a lot of wallowing and oscillation of the spring from its low spring rate. you may be tempted to put smaller bags up front because they dont require as much work, large diameter bags need a lot of room, but small bags with all that weight will need 100+ PSI to even start raising the truck, your war is over before its begun.

run separate air valves for each corner so air doesnt swap side to side in turns. run enough reserve tank to fully lift the truck once in case of a dead compressor, run more than enough compressors to recharge reserve in short time (look into engine driven compressors, 45 second from dead empty!) and drain the TANK for water once a month (condensation ends up in the TANK, not in a water trap between the compressor and tank, where is your water separator on your home compressor?). water makes compressors work harder. use check valves on the compressor (most leader hoses have them built in) and on fill valves (an empty tank will empty the bags!).

air suspension is very reliable, can be very comfortable, and still have good performance if set up correctly. too many guys will try to find the cheapest way to have all of that, but being cheap will be discouraging.

source: bagged many cars and trucks, owned even ore bagged cars and trucks.

[blazer2007]

I like static for daily driver, one less thing to go wrong. I have static on my daily and bags on my sunny weekend ride

[uppster]

Thanks Joedoh, that is the kind of info for learning. I appreciate it

[Stormin08]

my truck was setup (project widebody) http://67-72chevytrucks.com/vboard/s...d.php?t=771061
has the following...
4th gen F-body Shockwaves up front, w/ 2 " drop spindle
KP 6-link in the rear
controlled by accuair e-level

i can get the front up to stock minus 2" for the spindle.

for a weekend brusier the air is awesome...wouldnt be bad for a daily driver...IF YOU BATTERY is strong. but if you loose power and do not have a manual shrader inline...your done. it is a fight to get the truck up for service.

my dailys will all be static !

[cornerstone]

Yes, Thanks Joedoh. Your explanation clarified a few things for me. I've never owned an air ride car or truck, and decided to make my current project my first. I've kind of lost the desire to go forward with my air set up since it's taken me so much longer to complete my truck than I expected. I still plan on giving it the old college try, but if it gives me much trouble, I'll probably yank it all out and buy a complete static kit with a 4/6 drop. I'm thinking possibly ride tech.

You've got me a bit concerned since I have all 4 corners on 7" dominators. I really do want a super smooth ride, which is why I went with air, but I may need to make some changes to get what I will be happy with.

[SCOTI]

Originally Posted by cornerstone

Yes, Thanks Joedoh. Your explanation clarified a few things for me. I've never owned an air ride car or truck, and decided to make my current project my first. I've kind of lost the desire to go forward with my air set up since it's taken me so much longer to complete my truck than I expected. I still plan on giving it the old college try, but if it gives me much trouble, I'll probably yank it all out and buy a complete static kit with a 4/6 drop. I'm thinking possibly ride tech.

You've got me a bit concerned since I have all 4 corners on 7" dominators. I really do want a super smooth ride, which is why I went with air, but I may need to make some changes to get what I will be happy with.

Independent control @ each corner is best as mentioned.

Control can be complicated electronics or manual paddle valves. You pay much more for the benefits that come with electronic control but you're also open to all the standard issues a manual system can have (leaks) w/the electronics issues on top (switches that fail, solenoids that stick, ECU's that don't work right because of a ground/power/voltage issue).

You 'gotta pick your battles.

For my manual systems, I have a simple Schrader valve Tee'd into the tank to fill the supply line/s that go to my control valves (mine is set-up as F/R). The Schraders are placed where I can access them easy enough. I can use a portable air tank & transfer air from tank to tank if necessary or use a butt connecter to use the portable tank as the air source. It's all in how you design/build the set-up.

As for 7" bags @ all 4-corners..... It's do-able. But, the rears might not be @ an optimum pressure for the ride height you want which can impact ride quality (can doesn't mean it will). Again.... It all depends on how you design/build the set-up.

The main thing I dislike about the budget/manual version is the repeatability for alignments benefits. 90psi @ 6am/60°F does not yield the same height as 90psi @ 6pm/90°F. That difference impacts your heights which impacts your alignment. I don't worry too much for short in town drives but if I plan to be on the road (highway for certain), I always set the corners w/a tape measure.