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Discussion Starter #1
Anyone ever tried it??? I'm using the standard running gear and frame of a 1987 Chevy P30 step van..... thinking about getting rid of the leafs in favor for air ride and a 4 link.. any thoughts on this?
 

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Isuzu reliability tester
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Correct me if I am wrong but isnt that chassis very similar to a standard chevy 1 ton truck? If it is then it has been done a thousand times and I bet air ride has a kit for it. If not is pretty simple to make your own kit using a universal kit from air ride, just do some measuring and weld it up, air ride tech can walk you through the needed measuring parts so you get your bars the right length and in the correct places.
 

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Discussion Starter #3
And there in lies my problem... I can find stuff all day long for a 1988 Chevy.... but nothing for a 1987.....
 

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Discussion Starter #4
Hmmmmm

It says 1973 - 1992 Chevy C30.....


only $1900 too....... :confused:

 

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I have a funny feeling it would either fit the 87 or only need minor mods to make it fit, could save alot of fab time. Honestly making an air back setup is very simple once you do the proper research. I looked into it for a while since I was going to do a triangulated 4 link in my truck. I have some programs for figuring things out if you want I can send them to you. Just need your email. I am about 98% sure that you could build a nice air bag setup for about $650 complete, probably even less if I spent a little time looking. I would look at a 4 link kit from suicidedoors.com they make awsome products and are cheap.Then just buy some replacement shocks and some $65 standard airbags, and call it a day. 1 weekend should be all you need to get it all setup and installed. Let me know if you need any help with it.
 

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There are several companies out there that make 4 link bracketry and mounts and anything you can think of to put this kind of stuff together.

If you want some beefy components, something for a 1 ton that you plan on tow/haul with you will want to be looking at the stuff geared towards rock crawlers and extreme off roaders. The parts are built a lot beefier and are meant to take pounding and extreme abuse.

At my shop we deal with Poly Performance to get alot of this type of prefab parts they have some really handy and well built prefabbed brackets, trusses, mounts, and such as well as kit packages and they are mail order as well.
 

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correct me if im wrong but 77-86 is essecinally the same and 87-92 is all pretty much the same? so an 88 would probably bolt right in.
 

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Old-Topic but maybe this could help..

- 1973-1987 OBS GM pickup (C/K 10,20) were for the most part all alike with the exception of engine and axle options, Updated accessories and trim etc..
( however the K30/K35 or C/30 ran up to 1991 and had the OBS with the newer TBI engine and Trans. options from 1987-1991)

- 1988-1998 was of coarse the IFS era except for the K5 Blazer which was OBS from 88-91.


You should be able to source your system using the 1987 or even a 1991 listing for anythign that was C/K 30. I am not sure of the exact frame differences with the P series Frame but I'm fairly certain a small amount of modification would make it work for your chassis!!

Good Luck,
WILL
 

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Discussion Starter #10
Is this a true statement for the most part guys?


"One thing you can do is measure from the leaf spinger hanger bolt (center)
to the center of the axle & that'll be a good length for the parallel bars..
"


Never done a parallel bar set up before.
 

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I haven't done one yet either, but when I think about the geometry I conclude the following:

The parallel bars of the same length will maintain a constant pinion angle throughout the suspension travel.

Short bars will limit useful travel, may be a harsher ride?

Long bars let the axle move more nearly straight up and down in comparison to short bars. The longer the bars the more involved in making them sufficiently stiff so they don't bend or buckle. Longer bars are heavier and add to unsprung weight..

About half the length of the leaf spring seems like a good rule of thumb, this will give the new suspension travel similar characteristics to the stock suspension (with added benefit of unchanging pinion angle).

I think longer the better within reason, perhaps 6-8" longer than stock if you have room? Although if you won't have much travel then stock or shorter should be fine.

Again, I have no experience in this, these are just my first thoughts on the subject.

Grigg
 

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Discussion Starter #12
I'm not C-channeling the frame or anything... I only have 6" of clearance from the top of the axle to the bottom of the frame so thats all I'm going to get.... and I cant think of a difference if its sitting on bumpstops on the leaf springs...whats the difference if its sitting on bumpstops with a 4 link.
 

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Either way it's sitting on the bump stops. another thing to consider is you want your ride height to sit in the middle of the bag.
ex:
bag compressed 4"
extended 14"
throw=10"
ride height 9"

this will give you the best ride quality and remember when you load up your truck you inflate the bags to hold the extra weight at the same height as when it is empty.

Edit:
I also forgot to mention that a bolt is kit like the one shown won't work because it is made to bolt to the spring perches on a regular truck frame and axle. The p30 is set up with a cab and chassis axle which is narrower and has a shorter distance between the perches.
 

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Hi, A guy in the MPLS-ST PAUL area called crazy talk customs builds 4 bar setups. My son ordered just what he wanted from him and installed it himself, it's a good looking setup and should work great. The parts are plenty heavy for a 1 ton chassis. Brad.
 

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Why use a parallel and panhard instead of a triangulated 4 link? I have been looking at Kelderman's site at some of their retrofits and they're all parallel with a panhard. Most cars are running a triangulated setup, why the difference on trucks, any ideas? I am looking at bagging my p30 as well. 6" is a pretty nice drop for making it look cool.
 

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Old-Topic but maybe this could help..

- 1973-1987 OBS GM pickup (C/K 10,20) were for the most part all alike with the exception of engine and axle options, Updated accessories and trim etc..
( however the K30/K35 or C/30 ran up to 1991 and had the OBS with the newer TBI engine and Trans. options from 1987-1991)

- 1988-1998 was of coarse the IFS era except for the K5 Blazer which was OBS from 88-91.


You should be able to source your system using the 1987 or even a 1991 listing for anythign that was C/K 30. I am not sure of the exact frame differences with the P series Frame but I'm fairly certain a small amount of modification would make it work for your chassis!!

Good Luck,
WILL
the suburbans and crew cabs stayed square body till 91 also.



47, fwiw you could swap in a 60-72 trailing arm suspension fairly easily, almost bolt in. the air ride is super easy to add to that.
 

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X2 on the trailing arm being easy to swap in (if you're comparing home fab, to home fab).

Lunacy, the underside of a passenger car is much more crowded than under a truck. The trunk of a car isn't intended to haul as much (weight wise) as a pickup in the bed.

Even if they did it's a much larger difference between loaded and unloaded and a triangulated 4 link (built as cars are using) only works well within a certain range of ride height, where as the parallel W/ panhard is more forgiving (less likely to bind). Admittely not as critical with airbags (as you can adjust them to suit the loading).
 

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Discussion Starter #18
Note for search reference only, these pictures will also appear in my build thread, but I prefer to attempt to keep valid returns on 'Searches'

Enjoy guys.... all done cept the shock mounts.....

I was really dissapointed in how the panhard bar came out.... but I had no choice but to accept the angle.... the bags/brackets prevented me from placing them elsewhere...... good thing this truck won't be going anywhere fast or cornering at Indy..... it sucks.... but nothing I can do........


Panhard bar at slammed


4Link Slammed


4 Link at Ride Height....


Panhard Bar at ride Height





There will be 1.5" spacer under the bags so they bump stop with the frame hitting the axle or jsut before....





Comments welcome......

~M
 

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Two things I would change. Both your panhard mounts should have a little more meat, they are under a lot of stress and you don't want them ripping off.

Second, you should add some reinforcement to spread the load inside the c-channel directly above the airbags, or you may see the bottom start curling up over time.


All in all, looks pretty badass!
 

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you could move the panhard bar forward to the front of the axel tube and have better angles, also I think you should have the bolt at the axel end of the bar in double shear. It would be easy if you move the bar forward and mount the bolt horizontal. lookin` realllly GOOD !!
 
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