quarter elliptic rear suspension

Looks very much like the set up on the Rear of my Austin Healey Sprite (1960) However as noted above the for the springs to be mountet to the axle they would need to be stacked the other way. I believe the way they are shown the only spring that would be working under compression would be the main leaf. The spring eye hear is mounted into a bracket on the axle, sticking up and down equally, the top one mounting the upper locating link also bolted to a pocket in the chassis. The A/H setup is a unibody deal.

I got my car after it had been run in hilclimbs and auto crosses. The rear of the car had been lowered by a simple restack of the leaves of the springs. This also softend up the suspension as those repositioned short leaves mearly acted as spacers and were basically removed from the springing action. But they are located in a pocket in the sub frame. They are arched downward from the chassis tot he axle when unloaded. So if you want to mount them that way I think the shorter leaves need to be above the main which would add their resistance as the axle moves up under compression. Part of the AH suspension was a rebound strap on each side. These limited the drop of the axle whan unloaded. Attached is a link to the schematic. Part of this setup which ever way the spring are mounted should be a PANHARD link. Diagonally mounted from one side of axle to the frame opposite.

 

Ok,been there done this a few years ago.I did the same thing you have drawn up but did this on a mini truck.I works and rides like a dream.If you look at a Peterbilt Low leaf suspension it's basicaly the same thing and thats where I got the idea.But unless you are running airbags or coilovers with it it ain't going to work,the axle will just lay up aginst the frame rail..By cutting off the spring pack behind the axle all you have done is make a so called pivot piont or a lower link bar.If you add a top bar and a panhard bar you basicaly have something that works as a four bar.
Like I said add airbags or coilovers and it will work.And with the airbags it just seems to float down the highway.I would doit agian.

 

Notice the number of leaf clamps used even in a low powered Sprite?
Those are needed to keep the spring acting as a single unit instead of just the main leaf absorbing acceleration forces and deflecting or breaking.
Imagine a large engine and sticky tires!

If I HAD to stick with a 1/4 elliptic leaf/2 link setup in something I was building, I'd use the springs as the UPPER links and have them in tension under acceleration. Under braking they wouldn't be as heavily loaded in compression due to the front brakes doing most of the work.
The addition of a military wrap second leaf would give an additional safety margin if you were worried about opening up the spring eye due to the load...although normally mounted leaf spring eyes (think drag early Camaro...)would see much the same load and they don't have problems.

As far as a strap for axle extension control, I can see it for a lever action shock like the Sprite, but a correctly mounted tube shock would make it unnecessary.
Most any coil spring rear suspension uses the shock alone to limit axle extension and prevent the spring from popping out.

Bottom line is that having the ABILITY to use a 1/4 Elliptic spring as a control link in a drag race suspension doesn't make it the best, most reliable, most adjustable or the more cost effective setup for the role.

Use a 1/4 elliptic springs and shackles to the axle for the bouncey bits if you want, but use a proper 4 link setup along with it to get the easy (once you get some experience) adjustability and predictable, consistant reaction you need on the strip.

 

The design in the drawing from Pinkees RPU is the same basic design that I was talking about although mine was a bit less refined. You still can't knock the success of 100K plus miles.

 

Not quite. Pinkee has his spring pack bolted to the frame, not the axle. He is running a traditional quarter-eliptical setup with the addition of an upper link.

The main problem with your idea is where the spring-eye is located. There is nothing stopping the spring-eye from rotating around its bushing as the axle gets pushed up or down. If you reverse the spring, it will work.

 

Recheck what I said. My roadster was done the same way pinkees cars is done only with the spring on top and the bar on the bottom. My spring was bolted to the frame with the eye on the axle. Maybe I didn't make myself clear. But I should know I built it.

 

Hmm, yeah. Except any engineering and adjustments go right out the window the minute you wind the axle up on a launch....and you can't properly calculate any of that stuff anyhow when your lower suspension link is a spring.

if you're worried about tuning for drag racing, and don't want the look of conventional leaf springs, the correct answer is a three or four link with coilovers. Course, when it comes to hardcore drag racing, a typical traditional hotrod doesn't have the correct weight distribution to make a 4 link work right.

So build a drag car, or build a hot rod. And turn the damn springs around at least

 

According to the drawing you posted, you can replicate this exact suspension very easily. Go up to a Chevy Silverado and bolt on an upper link as you have it in the diagram. Cut the leaf spring right behind axle. Voila. Instant tail dragger.

 

so wait..then to do this,as i would like on the front of a car,i can just use the pin hole to bolt it to the chassis and put a u-bolt in front of that and it's mounted?of course the u-bolt is through the mount as well.why does this seem way more simple then i think it is?and as not to steal the thread,i don't think it would work without coilovers and that kinda defetes the point,right?plus,i gotta believe somebody on here could use those springs for something better then just cuttin um' up just to see.i'de say,if ya realy want to try it,go to the local junkyard and grab some cheap,whatever springs,cut them and bolt um up ruff.at least it'll give ya an idea if it'll work.

 

Gotta agree with 29MurrayTub here, that the big issue is unsprung weight. You want the fat end of the spring bundle bolted to the frame, not bouncing around with the axle.

Since the upper link keeps your axle from rotating, the spring will need to bend (do its job) as the axle moves up and down, and your setup will work.

Its kinda hard to visualize, but your setup is really the same as having the spring bolted to the frame, just with the whole setup turned upside down. If you flip your sketch over, draw the frame where your axle is and the axle where your frame is, it will look familiar and workable. The forces will be the same.

The unsprung weight thing (thanx, 29MurrayTub) is why you would not like it.

 

In addition to this, here's some shots of the rear end on a current project we're working on. These pics were taken pre-shock mount as well. I'll see if I can't nab some new ones.

 

I think the guys idea will work very well, and would allow the use of Cal tracs or other bar type traction assistance although I don't think he'll really need it.

Not only will it have instant center adjustment,but will allow preload adjustment in the extreme.

My only caution would be to run a one piece housing(9" or 8 3/4 Crhy.) or fully welded axle housings if I was gonna run a Chev or Dana 60 style rear

There was a 30's Hudson sedan here in Duncan America with a suspension almost identical to your drawing back when Ducan had a drag strip.The dragstrip was oiled dirt and the story is that old Hudson would hook right up,even on those shitty old tires back then.Even pull the front wheels some on occasion and hand alot of guys that thought they were fast an unexpected spankin'.

The top bar will be in tension not compression.

I also think the shocks need to be mounted in back of the housing to dampen the wind up of the spring.The extension is normally stiffer than the bump.

Oh and one other thing.I think a wishbone type top link with quality rod ends would also be cool because it would eliminate the need for a panhard bar and the attendant suspension"shuttle associated with it.

I like the Idea all around and have been kickin' it around myself I think it's .Welcome to the outside of the box.

When you pull the trigger on that thing the rise is gonna make you feel like you've got an elevator under your arse.

I say go for it and silence the naysayers.

 

the way it is pictured it wont hold car up it is like a 4-link that way you need to clamp the spring on frame and have eye attached to rear but wont work the way you have it