Re Shackle reversal thoughts

[Terry Rust <trust@domain.elided>]

>
>>I'll throw my $.02 into this discussion, but since my first hand experience
>>is all Jeep, you may want to skip over this.
>
 Again, let me emphasize that my experience is all Jeep and may not apply
100% to a Scout's heavier construction.

>And I'll see what else I can remember from past discussions (no experience
>here... YET)
>
>>As Tom mentioned, the spring eyes want to be the same verticle distance
>>from the ground (or some datum) when finished, while this is not 100% kill
>>ya if ya mess up, it ought to be as close as is easy, you can use slightly
>>shorter shackles to twist the front yoke up instead of shims, but beware of
>>going to far. Obviously the fronts need to be even with each other at both
>>ends too.
>
>If your springs are NOT "level", you'll get some strange behavior when the
>springs compress/uncompress.. typically the spring compresses UPwards, but
>if you "tip" the spring at rest, say the front is higher than the rear, the
>spring will compress Up and REARWARD, making the old "tire hits the backside
>of the fender" problem even worse, and possibly hurting your overall
>articulation setup.
>
>Granted, as Terry mentioned, it would take a fair bit of un-levelness to
>cause any big problems, but this is why.
>
FWIW, my 74 CJ5 has about a 1" difference in front to rear spring eye
height, the rear being slightly higher than the front, I have no additional
handling problems (Remember that CJ5s are NOT noted for their precise
handling! Especially with a lift and 33s) or funniness with tire wear or
anything. That said I have seen some hatchet jobs where the monkeys just
bolted the springs into the existing shackle mount and hung shackles from
the rear fixed mount, big NFG as far as I'm concerned.

>Also keep in mind the drag link... if you have any type of lift, it's
>probably not very happy with you to begin with.. then you want to tip the
>axle end of the drag link and put it at an angle *too*??  Not only would we
>be making the ball joints in the drag link ends to work harder than ever,
>but your steering mechanism isn't exactly parallel like it should be, either.
>
>As I think about this, turning the knuckles causes this "problem" too.. but,
>again, we're talking 4 degrees with a knuckle twist, and provided your
>springs aren't too far off, they won't be causing any radical changes here
>either..
>
The steering linkage issues will be the same regardless of how a lift is
accomplished and should be considered and fixed appropriately.

>The short of it is, don't try to bolt the springs just below the front cross
>member and use a custom rear shackle.. you won't like the results!
>

As I mentioned before, this is a big NFG, and to add insult to injury,
wheelers everywhere will make fun of you!

>>Your axel will now move up and back vice up and forward so the axel should
>>end up slightly forward in the wheel well from where it is now, I use an
>>reassemble the pack. I've seen it done both ways and even combinations of
>>the two. The kits that are available for Jeeps now all use the fron tower
>>to re-locate the spring forward, FWIW.
>
>Willie Worthy had some real problems with his reverse shackle on TONTO.. he
>said he re-did his front spring towers two or three times to get things
>dialed in so the tires stopped trying to sit in the cab..
>
Harold Off is a big advocate of redrilling the mains to move the axel
forward, I've done it to mine without moving the mounting point forward, no
hits so far, no broken springs either, so far. Werkmeister has just the kit
and I don't think he has any hitting with 35s, if he does it's minimal
enough that it's not a problem. JB, My other buddy has done both, again
without any troubles on his scrambler, he has reverse shackles Nationals on
his CJ5 that move the axel forward, but it doesn't count since they're
truly custom units and I don't know haw he spec-ed the spring locating
holes.

>Terry, what about lift springs?  I've seen some measurements taken, and it
>seems lift springs, eye to eye, are shorter than the stockers.  My stock '77
>front end  springs seem to be about 44" long (rough tape measure job before
>work), while a set of Superlift 4" springs are rumored to be 41" long.. Jim
>Weed's reverse shackle plans space the spring eyes 43"..
>
This is sort of a sore point for me, I have always measured eye to eye
across the arch, I guess the "correct" way is to measure from locating pin
hole center to eye center. For my Jeeps (stock) it's equal, not all
vehicles are though. It seems that lift mfgs take stock length springs and
arch them deeper which, of course, shortens the distance across the arch,
this is what happened to us while trying to use the CJ springs in the 800.
Now conversly, as the stockers sag the distance across the arch will
increase, yours may have started out at 43"(or there abouts), or some of
the lift kit springs may be 42+ when installed and loaded. If you get
customs from National, triangle, alcan, or whoever, you should be able to
get whatever you want. In fact, a buddy has Nationals on a CJ5 that he
extended the frame rails front and rear to accomodate, the shackle for the
front springs and the fixed point for the rear springs are a foot or less
apart! Of course it ramps over 1000 and flexes really well. If I ever buy
another set of off the shelf springs I will use that info as part of the
decision criteria as to which brand i buy. More and more I believe that a
set of customs is money well spent if you do the homework and get them from
a decent outfit that understands what you want to do.
>I'm wondering if lift springs, being a little shorter, make up for this inch
>or so of forward relocation.
>
Shouldn't if the locating pin is in the center, it will stand the shackle
up more straight though  which increases the chance of getting them flipped
backwards.

>Also, I'm not sure if turning the springs around front/back helps the
>situation, or if anything strange happens because of the spring rates.  I
>know people use this tactic on the rear end to re-center the tires a little
>further back.

Again it depends on the spring design and the bushing in each end, full
sized jeeps have different geometry bushings at each end of the spring for
example which makes the mounts and shackles a different width from one
another.
>
>>Tom was, again, dead on with the need for a cross brace between the towers,
>>would tie the towers hard together and not make them boltable, but there
>>could be some value in that, just be sure to monitor the bolt holes for
>>wallowing out over time.
>
>I wasn't sure if I wanted it fixed or not.  An informal poll at the NWBinder
>Roundup showed half the trucks with and half without the brace (those that
>had reverse shackles, of course!)  I couldn't determine if there would be a
>time that I *want* those towers to flex or not..
>
>But, now that I've heard.. it gets WELDED together.. besides, what's another
>1" on the RTI anyhow compared to frame stress..

My feeling is that the more solid the better, but there are many ways to
skin this cat, maybe there is a really trick method that would allow for
the best of both.

Good luck, I hope to get the 800 RSed before it goes to live in Bozeman
this spring/summer. If i do I'll let y'all know how i did it.