1/4 ellip mount... (1 Viewer)

[woody]

Medusa and DogWalker have great spring pack mounts, recessed into the frame rails. I opted to try and make one that keeps the springs further outside for greater stability....but not sure on strength...any opinions?

(what's attached is experimental, just mocking up where it would go, and a general idea of what it would look like. 3/16" thick 3" x 10" frame-side plate, 1/4" thick plate to mount the pack, and full gusseting....)

any thoughts?

 

[Mace]

More support from above and you will be good to go..

But I kinda doubt that keeping the springs that far out will do much for stability..

I would thing that spring rate would do more..

Are you planning on a swaybar?

 

[woody]

hoping to avoid the swaybar...."most" rigs with 1/4's in the rear don't seem to need them, but never know.

And yea....the more I read/check, the more I lean towards just doing it Medusa-style....his is WAY too clean looking for me tho!! lol

 

[willsta2000]

IMO, the farther outboard your springs are, the more mechanical advantage the springs will have over compression and extention. Basically you'll have significantly more flex if you moved your spring packs inboard ~3" and mount them like Jack Rice's has his. You or I'd have to open a couple books to figure out the #'s on this and calculate some spring rates, but I think that having your springs where they are vs. inboard will make the difference between having 3 wheels on the ground vs. 4.
In your case, as everybody knows, it might help keep ALL your wheels on the ground!!

Granted I have no idea how stiff those van springs are, if that's what you're using.

 

[woody]

[quote author=willsta2000 link=board=12;threadid=9834;start=msg86919#msg86919 date=1073589073]
Granted I have no idea how stiff those van springs are, if that's what you're using.
[/quote]

"most" people doing this type of conversion are using 3/4 or 1-ton Ford pickup rear packs, which are wider and equally as thick as these....stiff is not a concern, but working to keep things balanced somewhat with the front is. I think these'll be a good compromise...but yer right, location does have a big effect!

 

[Eskimo]

much taller gusset's on the top of the mount, other than that, looks A-OK to me...

Gonna have the spring packs REAL close to the brakes, no?

 

[Mace]

Cool thing about 1/4 elip is that you really do not worry about articulation. Most times you need a limiting strap to keep everything from dropping out of sight.

Woody, say it with me.....

"Clean is not bad"
"clean is not bad"

 

[Medusa]

Like Jason, I don't believe that outboarding 1/4 elliptical springs really gives you any more stability. Unlike conventional leaf-spring suspensions where the spring pack is firmly bolted to the axle (and wider = more stable), the 1/4 elliptical spring is only very loosly connected to the axle. As shown on my junk, the "shackle" allows the spring eye to move both fore and aft and also from side to side. I think the ability to move from side to side negates any advantage you might gain from a stabiity perspective. In other words, since the springs do not "locate" the axle, the location of the springs on the axle does not play the role it does on the a traditional suspension. "Stability" and ride characteristics are determined by the link geometry, not by the position of the springs. More sprcifically the roll axis is going to play the largest role in lateral stability.

Having said all that, I don't think there is anything wrong with outboarding the springs if you have a wide enough axle. You will be asking the springs to move a lot more than they would have to if moved inward, but that is usually not a problem since they do move so much anyhow. I would make your mounts bigger -- use 1/4 for the scab plate and make it about twice as long. I would also use 3/8" plate to sandwich the spring pack and I would make sure they are well gussetted

 

[Radd Cruisers]

Jack, could you take some more shots of your linkage hooking at the other end. I like the the perches, never really seen that before. Looks like another Heim joint?

Dollar wise, way cheaper than coil overs?

If you desired you could switch with very little work to coil overs?

Rob

 

[woody]

http://darkwing.uoregon.edu/~jrice/cruiser/FJ45/Suspension/Springs.html

outta cover everything

 

[Texican]

Woody, I think you need to emulate the setups that work, cause a break here will sideline you, and we'll all get to watch "C" take you out..............and I'll gladly let her wheel my rig out.



Butch

 

[Radd Cruisers]

[http://darkwing.uoregon.edu/~jrice/cruiser/FJ45/Suspension/Springs.html

outta cover everything

Damn I was on his site and missed that section.



Thanks
Rob

 

[woody]

[quote author=Texican link=board=12;threadid=9834;start=msg87277#msg87277 date=1073620222].............and I'll gladly let her wheel my rig out.



[/quote]

finally....someone driving yer rig with some skills!

 

[Medusa]

I made the "pedistals" for the spring shackles by cutting the end off of a large AG heim joint and welding that to the base of the shackle. This design allows the axle to articulate without deforming the spring bushing or twisting the spring.

Dollar wise, way cheaper than coil overs?
Considerably, since good coil over shocks probably start at around $400 each.

If you desired you could switch with very little work to coil overs?
Sure... remove the springs, buy the coil overs and fabricate new mounting tabs for the shocks. The links would not change at all.

 

[woody]

I like the ag heim joint idea....I may do something similar, welding an ag heim to the axle housing and using a normal shackle with a sleeve....

BTW: Jack, I need to insist you not post your project photos here...your quality of work is such that none of us can attain it, and you make us look bad

The advantage to 1/4 elliptical is low cost and easy adjustability. Add/subtract a leaf to change spring rate. The advantage to regular coils is install work, they are usually easier to fab up mounts, but you lose the easy of rate adjustment. Coilovers are the best, but cost is an issue....someday, but not on this rig.

I also have an "issue" with mixing/matching spring types.....IMO, the best balance is achieved with all 4 corners running the same setup....I'm already hoping I can adjust the 1/4 packs to provide a relatively balanced articulation.

 

[fjcruiser]

[quote author=woody link=board=12;threadid=9834;start=msg87630#msg87630 date=1073666123]
BTW: Jack, I need to insist you not post your project photos here...your quality of work is such that none of us can attain it, and you make us look bad
[/quote]

Certainly a level of quality to strive for. I'd probably put my bed in the shop so I could wake every so often and look at it.

 

[Radd Cruisers]

BTW: Jack, I need to insist you not post your project photos here...your quality of work is such that none of us can attain it, and you make us look bad


I am sure Jack would agree you are doing a great job seeing as how its being done on your back.

From expierence with the body off, things are much easier to work on along with the fact you are able to see what you are doing plus no blind welding.

Keep the pics coming!!!!



Rob

 

[Medusa]

Does this mean that I am in the "Picture Band" ?? FAR OUT