ElPolacko...come to the help desk please......

[Roothawg]

Hey man, I have yet another chassis question for the Hamb resident chassis god.

I am planning on getting started on a 35-40 chassis for the shop truck. I am planning on pulling the Fly and a small 2 wheel trailer etc. What type of rear suspension would you suggest? I have wondered about the coil overs, air bags, etc.

It has reversed arch springs in it now and it really wouldn't hold any type of weight. I want an adjustable ride height depending on the weight of the load, so keep that in mind. No on board compressors though...no room and too much $$.

Thanks man.......

Root

[ELpolacko]

Just about any good four bar will do the job well, I wouldn't mess with the comercially available stuff as the lower bars would want to flex under towing loads.

A torque arm type of suspension is going to give you the most compliant ride and they are really compact for something you need to get low.

Damnit if I can't find my pictures. What I wanted to show was how we do the lower bars of a torque arm suspension. We make them out of 1" X 2" .120 wall box tube and weld on 2" .125 DOM tube by 1.5" long on either end. Then we use large poly bushings (ENE2072). The poly bushings need to be trimmed as when put together in pairs they are ment for a 2.5 or 3" wide sleeve. And a steel sleeve of 3/4" .090 wall tubing 2" long to push through the middle as a crush sleeve. 9/16" hardware is used to locate this stuff. IF you you 3/4" .120 use 1/2 hardware, either will work but I would like to see the heavier bolts in practice.

Here is a shot of a triangulated four bar using the same type of links,

AAAAAAAAAAAAAKKKKKKK, I can't seem to get a picture under the 70k limit without looking like shit so please bear with me.

[ELpolacko]

As far as bags go, use the tapered sleeve type. Trust me on this one you can mount them directly to the axle housing in several ways and still have good suspension travel. The Double convoluted style should not travel more than 3-4 inches total,,,,yeah I know you minitrucker types can make them travel six inches, but that screws them up and it takes so much more air pressure to move that last inch and harshens the ride quite a bit.

This should be a spring rate chart for a double convoulted bag, you get the picture quick.

[rickyracer1962]

polish engineering (tm)

[rickyracer1962]

another

[rickyracer1962]

last one

[Roothawg]

Ricky, what is the purpose of the center bar?
If you have the 2 side bars, they should locate the rear end right? I need to look at those again.

[Roothawg]

ElPolacko, so you are suggesting the bags as the way to go?

I will have to do some research since I have no idea what you are talking about.....on the difference in the bags.
Will they hold if you use a schrader valve setup? With no compressor or solenoids?

[rickyracer1962]

the long center bar is the torque arm, plants the tires very nicely!

[Roothawg]

How does it ride? Does that torque bar swivel in all directions? Like a U-joint?

[Roothawg]

I am definately gonna hafta study up on this....

[rickyracer1962]

i didnt ride in that truck, but i have ridden and driven the shop truck with the same set up. rides like a caddilac, handles better than any truck should be allow to, and transfers weight pretty neat when you get on it.

[Roothawg]

Just kinda wondering if it has to be triangulated or if three separate parallel legs would do the same thing?

Oh, and what about pinion angle? Would it change?

[ELpolacko]

been in and out here,


That center bar is the torque arm, it is mounted at the front with a shackle arangement to allow for and aft movement. That is taken care of by the two outside locating links. Works like this, the axles rotational force is using the arm to "lift" as close to the center of gravity as possible. The two locating links "push" the mass from behind, so you get the weight transfer of a ladder bar set up and the tire loading of a fourlink with the ride compliance similar to a triangulated four link.

Thank you ricky for the picks, that was the Ironwood truck.

[Tinbender]

Don't mean to butt in, but do you have any more shots of the torque arm mount in the front? Thanks.

[Roothawg]

Yeah I would like to see this "shackle" that you are talking about.

[Roothawg]

bttt

[CURIOUS RASH]

<font color="green">HHHHMMMMMM.....????

[ QUOTE ]
We don't care how they do it in California.....

[/ QUOTE ]

Where ya from Ricky? </font>

[Roothawg]

Shut up fag..........

[Roothawg]

BTW, ElP did it in AZ.

[CURIOUS RASH]

[ QUOTE ]
Ricky, what is the purpose of the center bar?


[/ QUOTE ] <font color="green"> UHMKAY? </font>

[ELpolacko]

to further cloud the mystery or to make it perfectly clear, Ricky used to work for me,, here in AZ

55Safari is supposed to take some shots of Chris Sheltons truck tomorrow and post them for you guys.

[ELpolacko]

Best I can do for you right now is this,,


The piece you see above the circle is the clamp on transmission mount, the link mounts into a socket in the front of the torque arm and goes up to a ridgid mount on the frame.

[flt-blk]

I have never seen a link like that to the spring, pretty tricky there ElP.

TZ

[tomslik]

peek under some 'vettes...

[CURIOUS RASH]

<font color="green">That is spmeurty work there ElP.

I'm just busting Root's balls and he knows it.

Gotta keep him on his toes, sharpen his wit.

He's coming along nicely.

RASHY </font>

[ELpolacko]

[ QUOTE ]
peek under some 'vettes...

[/ QUOTE ]

For the rear spring mount, yes that is how Corvette stuff is done. However Corvettes do not have torque arms. The have an aluminum beam connecting the transmission and rear differential together. Why? Ever notice that the cars with that beam connecting the two do not have transmission mounts or pinion mounts? Kind of a neat clean way to mount the drivetrain and isolate it from the passenger compartment. Part of what makes a Corvette special and some of the first stuff Street Rodders eliminate when they transfer those parts into thier Street Rods.

The torque arm isn't new and I can't lay claim to the idea, GM has been doing it for years. Some Vegas have a simmilar design and the 80's up F-body Camaro/Firebird have one too.

[Roothawg]

Thanks...any where I can go to study this setup?

Root

[ELpolacko]

other than to dig around unde an Fbody for a few minutes. I just took the idea and ran with it. The one pictured is the latest design. It took a few different "trys" to get it as clean looking as that, they all worked well enough as Ricky was saying.

[Roothawg]

Hate to beat a dead horse but...........

I just scored some of the coolest front mounts for my trailing arms. I'll post pics when I get home.

I just wonder if you have found that it makes any difference in the length of the trailing arms?
Also If I have more angle on the outside arms as far as triangulating would this have any affect on the stability?

Thanks again

Root

[Roothawg]

Sorry Bttt

[Roothawg]

Honest opinion...would this work or not?

[Roothawg]

Or this setup?

[ELpolacko]

Those are fine, the biggest problem I see with aftermarket triangulated four bars is the angle of the upper bars. Most manufacurers don't run the upper bars 90deg to each other. Add in some bushing flex and you have yourself some body sway. The next issue I would be concerned about is the tubing used on those lower bars, typicaly they use 1" X.156 wall tube tapped out for 3/4" 16 bar ends. Under towing loads you will flex those bad boys. I would run a minumum of 1.25" X .188 wall stuff.

Those shockwave deals are a slick set up, if you get the big ones that have something like 5+ inches of travel (part number SKW9000). The standard deal they try and push only have 2.5" of usable travel, that sucks!

[Roothawg]

So would the only problem actually be the tubing itself? The reason I ask is I could build my own setup if this design is acceptable. I know you do it for a living and I will try and send some green your way when I buy my parts. I just want a system that will be reliable and work well in the long run. Thanks

[Roothawg]

I guess my next question is do you have a setup for the 35-40 Ford? I didn't think to even ask if you had a pre-made kit with the larger tubing?....I looked on your site but didn't see anything.

[ELpolacko]

Sorry Root, dont have anything for that app. Copy away with my aproval!

[Dirk35]

Hey Root, if you havent seen that before, its really looks just like my old 83 camaro except for the single spring. You said you were wanting cheap. Look to mid 80s camaros for a nice 12 bolt posi rear with a torque arm, with a 3:73 with discs. You can usually get the whole car cheaper than you can the rear. And youll deffinitly be able to appreicate as much brakes as possible while hauling the fly with such a light truck pulling it.

Its an idea worth looking into, and for adjustability that your wanting (i.e. not a show stopper frame laying suspension), air shocks would suite the bill for trailering.

[Shiva69]

First go check out the pictures on Glen's site to see his torque arm setup

Second ElP has some articles in classic trucks showing that suspension setup. i have some pictures i'll try and find them all but here is a good pic to understand the torque arm setup


a bit more... you can look into doing a engine powered compressor with using a york AC pump. They can preasure up to 300 psi. if you want more info look up "on-board air" and "york air compressor" i hope that helps

Garth

[Crosley]

I looking at using the mentioned torque arm design on my Morris Minor. It will keep the floor a bit lower I think.


hopefully the traction will be there.

[Roothawg]

That pic helps Shiva...Thanx