ride height on airshocks

[diymirage]

Hey guys

working on the car this morning I noticed I had a broken airline in my rear shocks
I managed to relocate the fill valve and cut the line so everything works the way it should again

I have done some reading and it seems most people don't like airshocks on a mopar since they tend to counteract the natural arch of the springs

so, what is the proper way to get this set up, I there a pressure to set it for, or do I mearuse from the top of the fender arches down to get it to the proper ride height?

the car is a 71 duster that came with a /6 and 7 1/4 rear end
the springs that are on it are the same springs it (presumably) came with but the drivetrain is now 408-727, 83/4

 

[65Val]

I just put enough air to even up the ride height, usually only an inch or 2 of lift required. Thats about 30-40 lbs of air.

 

[Bad Sport]

I have done some reading and it seems most people don't like airshocks on a mopar since they tend to counteract the natural arch of the springs

The reason most people don't like them is because they can tear the sheet metal around the upper shock mount and then you got a problem.

Shocks aren't designed to hold the weight of the car, the springs are. That is the first thing I ripped off of mine when I got it and placed them in the circular file.

If they are going to stay, they MUST be plumbed independently. 2 shocks, 2 lines and 2 air fittings. If they are plumbed together the air can force out of one and into the other when cornering.

 

[mopowers]

Ditch the shitty air shocks and buy a set of decent springs. You'll be much happier.

 

[diymirage]

with winter almost here, I'm not looking to replace it, only to have it sit for 4 months
so right now I'm just trying to make it all work

as of now, there is only one filler valve for both shocks so I can see how that can cause some unwanted body roll


now, what would be the best way to level the car?
measure the fender arches?

 

[Bulldozer]

There is absolutely nothing wrong with air shocks when they are used correctly. If you install them on a rusty *** mount, blast 200 psi in them and load the trunk with bricks, you are going to have problems. Ive been using them for many years and I've never had a single issue. I fill them up to around 100 psi with the weight off the back of the car, set it down and let the air out until I like the height. I also buy them extra long so that I can get a little lift and still have a smooth ride because it only takes 50 psi or so to get there. I also plumb them independently as Bruce states

 

[gdrill]

...........:d

 

[Inertia]

There is absolutely nothing wrong with air shocks when they are used correctly. If you install them on a rusty *** mount, blast 200 psi in them and load the trunk with bricks, you are going to have problems. Ive been using them for many years and I've never had a single issue. I fill them up to around 100 psi with the weight off the back of the car, set it down and let the air out until I like the height. I also buy them extra long so that I can get a little lift and still have a smooth ride because it only takes 50 psi or so to get there. I also plumb them independently as Bruce states

...........:d

Thank-you both..

I'm sure there's an "Urban Legend" about a rusty POS R/Runner out there with the bricks in the trunk that DID wreck the rear mounts,... same as the boogie man,, and whatever's scary under your bed at night..

Fact is,, "back in the day" a lotta the fancy suspension stuff didn't exist ,, but Max Wedges, and quick Mopars etc did..

Mid sixty's, my wage $3.65 an hour, and an avid racer,, I couldn't afford the SS Spings.. But lotsa Rod mags and other literature taught us,, that by having a loosy-goosy front end,, and that with a pinion snubber,, clamping the front of the rear springs,, and using dual inlet air-shocks, a little more air in the passenger side shock.. we could pre-load our rear ends much like modern adjustable rear-end suspensions.. and hook better than without.. For racing,. IIRC ,, I'd run like 12 lbs left/side,, 20ish r/side.. not a lot,, but enuff.. and adjust it by doing little burnouts,, then comparing the tire marks.. Adjust tire air,, and shock pressure as nec..

I ran with 20 ish lbs pressure on the street (I didn't care for the "ski jump" look, I was after weight transfer) unless I had fat friends in the back-seat, a complete motor in pieces in the trunk,, or my 16' ski boat filled with camping gear,, then the air pressure went up,, to maybe 50 or 60lbs.. as nec..

For at least 10 successive seasons,, My 69 Dart carried four adults, a kid, a dog, a trunk full of camping gear,, towing a 16' ski boat/motor across the dreaded "Coquihalla Hiway",, and came back from the "Okanagan" with the 16' boat and every spare inch of car filled with fruit,, hundreds of pounds of it, cherries, peaches, apricots., in a Dart,, using air shocks,, for over 10 yrs.. (with 10 inch drum brakes)..

That car (and others) are driving today with air shocks,, and do not have damaged upper shock mounts..

I wouldn't hesitate to install them today,, and never had reason to regret using them in the past..

I installed lotsa air shocks, then maintained these vehicles thru the decades, and have never seen anything close to a damaged upper mount,,

I have no doubt there's an East Coast Rusty POS,, that may have damage mounts,, but that's likely not the worst thing wrong with it.

jmo.

 

[abodyjoe]

use as little air as possible. i used them on my dart for many years with no issues. hell it even went a 1.69 60" at the track with air shocks..

 

[AJ/FormS]

I have used a little air shock with a little extra spring, to make a nice dual purpose vehicle. It can also be used to intimidate other streeters. My current combo does not use them. I chose instead to re-spring it to a lowered ride height, so that I can kinda fly around corners.
In it's earliest iteration it did have air shocks, for the intimidation factor. It has never 60 footed well, with it's street suspension, but at that time, it looked the part.( With the lowered ride height, it was/is now,very unassuming.)With the air-shock adjustability I could run a little softer spring for day-to-day, ride comfort. Unfortunately, my airshocks were only adjustable as to ride height, and not for damping, so they were not on the car long. I did consider auxiliary air bags,but could not justify the price. Instead I modded the springs, and changed my poser-attitude, and live with the ride.

As to leveling the car, this is what I do.
First I make sure all the tire pressures are the same from side to side, and that the front tires are twins and the rears also are, and that the car is empty of luggage and such. Then I jack the car up under the center of the pumpkin. I use a block of wood on the jack-pad and a cross-pin from an old rearend laying longtitudinally on the block, across the woodgrain.I get the wheels up about an inch. This allows the car to rock on the pin, and frees the chassis from any preload the rear springs may be exercising. Then I first level the front. I open the hood and put a level on the rad core support. If the front is not level, I first measure the front ride height, on the cars centerline, cuz I will want to keep this as a control. You can use any convenient point on the vehicle centerline. I use a block of 4X4 wood, trimmed to fit under the lowest part of the center of the K. The rear height needs to remain the same throughout this exercise.
Then I adjust BOTH of the T-bars,equally, one up, and the other down, a little atta time to get the bubble to come home. This does not usually take much. At one time, I used a spacer under the LCA inner pivots (which is the right way to do this), but I found that on my car the core-support works fine and saves a lot of wear and tear on this old body. When it gets level, I recheck that the rear ride height has not changed, and then the front height.
So, I should interject here that I could have used the wheel openings. But the problem with that is that the openings are constantly changing from front to back, AND more importantly, there is just no way, after nearly 50 years, of knowing where the chassis is,compared to where the lips are. AFTER the core-support is levelled, I can find two points on the lips that measure the same, and reference those points, and hereafter I can use those two points.
Now I can go to the rear. So, I drop it down, and go look at the level. If it remains where I set it, it's golden. If not, I bring that level around to the back. Under the rear bumper is a cross bar spanning the distance between the frame rails. This bar is welded to the trunk floor. It would seem logical to use this bar, inside the trunk as a reference for leveling. Unfortunately, in my Barracuda at least, there is just no good way of doing that. At the back of my car there is just no good place to use a level. So instead I measure from the rear spring perches to the flat cement floor in my garage. Since my frame at that point is not level in the for and aft direction the exact points used are a bit critical. But hey, it's a streeter, if it's within a few fractions, it's good to go.( now if you don't have a flat level floor, you will have to create one. A simple solution is to use a piece of plywood or some other flat material, to span between the perches, and 3 or more inches wide.Just lay it on the ground and with the level, shim it flat in all directions, and bingo.,measure off that.)
So I put the level back on the core-support, and measure the points,back at the perches. Then jack the low side up, at the bumper, until the bubble comes home. Then re-measure the points. Doing some math tells me what needs to be done back here. I have an Optima battery mounted in the trunk,on the right, just behind the tub.My springs also have an overload sub-main leaf, spanning from eye to eye. I had to install one extra, short leaf on the right, to bring the bubble home. As it sits now, the car is level from side to side at both ends. And the front lips are even at the referenced marks. The rear lips, however are not. One side had a new quarter installed back in 98. My guess is that it was not installed perfectly. It ain't out by much.
Now I should mention that the reference marks I made at the front are a handy way of keeping an eye on sagging T-bars, and when minorly adjusting the ride height.
That's how I did it. Your results may vary.

PS. yes you can adjust the rear side to side height with air pressure. But now you are tweaking the ride height AND the ride quality, and perhaps to some degree the cornering .You can also, if not concerned with cornering, run both shocks off the same filler. Or if you do like cornering, you can install a restrictor, in the balance line between the shocks. It just takes a lil longer for the ride height to stabilize after a pressure change. But honestly, for a streeter, I didn't notice a cornering change after switching to individual lines. With the rearend up, cornering is a wild ride anyway. Unless if your engine is lazy or underpowered. But with 6 liters(367 cubes),of Hi-Po V8 torque, cornering on city streets requires a great deal of self-restraint anyway. Not like that puny teener I used to put in there for winter,lol.