2 link question

[Silverslk]

There should be some sort of internet protocol where Sarcasm gets put in italics or something. would stop lots of E-fights (scared apple would sue if called i-fights). hahaha

[Smart Alex]

I fix peoples stuff thats been designed in different forms of CAD.

Full scale real layout is how you do it.

Half scale works good too.

[AussieRod]

Rod - I can't say for 100% sure, but I think you might be missing some sarcasm in Mike's post. My guess is he knows Kyle & is poking fun a bit. Just like the way others on here poke fun if we know each other.

Still, your point is valid, just not sure Mikey was being malicious with his comment

Steve, I am aware Mike is probably being sarcastic, but after the LED light thing in Parts, I didnt want it getting out of hand again, for whatever reason

[ChaseTruck754]

I'm still trying to figure out WTF happened there.

I do hear you on keepin the peace though. We've been good thus far on this site for keeping it mellow. So far we have a pretty tight knit group with no real drama. As the site grows & more & more people start posting we'll have to work to keep it that way.

[AussieRod]

Not sure WTF happened there, either, and sure really dont want to. I'm just concerned it might get out of hand again. Cheers all

[kylesgorter]

ya mike is giving me shit about some discussions from dezertrangers from years ago. I did a few sets of cast ranger beams back then that were over thought, over built etc to make up for the fact that they were basically junk. No failures tho! Ive done 20x more ranger setups with forged or custom beams but still the fact I did a few cast sets haunts me hahaha.

My point specifically here is that the geometry of the 64 kit is nowhere near the same as the spring over type configuations. A lot of the spring packs mentioned here are being used with stock brackets and mounting locations. Having had more than a little firsthand experience with the giant setup I will say that I do not think a 2 link or upper wishbone is feasible, at least not if using the maximum amount of movement the springs are capable of. 21-22in of travel is actually quite a difference from the 16-17 that a lot of bronco owners get especially when some of that 16-17 is in negative arch and over 60% of that movement is also droop. If any of you guys were able to just set a g70 gen 2 pack next to a standard spring over pack you will see there is no comparison they are completely different. So, just because the 2 links supposedly work well with the spring over packs doesnt mean the same would apply with the giant setup which is what the original post was about

Ive setup one of these 2 links before with j40 pack and there was binding. If people are using their setups and reporting added performance and no issues then their setup must be different than the one I setup or the spring packs work differently. Im not trying to dicount Autofab or Southwest in any way I know those two names are protected around here but I am reporting from personal experience from vehicles Ive built and driven.

I am all for anything that works well in the dirt. I also will add that on paper things are different that in real life function and I am in no way to proud to admit if I am wrong. Like I said ie neer messed with f53's before were it seems a lot of people on here have and it also seems that very few if any have any realtme expereince with the 64in kit.

Next time theres a meet at pismo we will have to run some broncos or do some ride swaps and get this figured out lol.

[kylesgorter]

and as for the sarcasm thing.... mikey and i are from DR. its a whole other ball game over there so hurting my feelings just doesnt happen on internet forums. In my eyes theres only my experience. If I EXPERIENCE a bronco using a 2 link setup with a 64 kit and it works well then i know for sure no matter what anyone (including myself) has said. I like discussions and I love to talk tech as much as i like talkin smack its all part of the fun.

[AussieRod]

Its all cool, Kyle. Agreed, the goemetry between SO and SU is very different, and thats the reason you would most likely NOT need the 2 link. The way the axle tube applies leverage to the spring pack is completely different from one to the other. In SO (spring over), removing the factory block and clocking the mounting pad on the axle housing is important to making the 2 link work with MINIMAL binding. The closer the axle tube is to the centre of the spring pack, the less leverage it can apply to the spring in accelleration and braking. I must admit, I am not a fan of using a 2WD 2.5" F53 pack on a vehicle that should be using a 3" J40 pack. The extra width (and strength) of the wider leaf resists sway better and is stronger in resisting the wrapping forces that occur. If I am correct, Geoff's leaf packs have the ends closer together at the front of the spring than at the rear. That also helps. The first few leaves in a spring pack do the most work absorbing wrap-up, the shorter leaves come into play as the pack is compressed to add rate. The length and thickness of these shorter leaves decide that rate rise. The multi thin leaf packs add rate very progressively to give a smooth controlled rate rise and controllability, and ease to valve your shocks / bypasses. SU, with its different goemetry and the way the axle housing applies torque to the pack, can controll the wrap-up forces better and in lightly loaded vehicles, wont require the assistance of the 2 link. Thats my 2 cents, I stand corrected on any points.

[kylesgorter]

some really good info there! the 64's have a full military wrap with a second top leaf that is 1/2 as long as the main leaf and terminates just behind the rear of the spring perch. Geoff told me it was there to control wrap mainly but was also designed to eliminate breakage of the main leaf. I belive autofab mentions on the site that the main need for the 2 link is to keep from breaking leaves as a result of fatigue. I will say the whole setup works AMAZING! Never had any issues on the trucks and bronco I put them on.

back to topic tho, is there anyone on here that has any experience with upper wishbones on broncos with healthy travel numbers? maybe some good pics? vetran racer buddy of mine is a big fan of upper link setups when space is appropriate and according to him you can make the leaf springs work better and drop out quicker by adjusting the upper link. For this reason he said all heims is best to have some adjustment.

Also, anyone out there running a Giant 64 kit with a 2 link speak up! post some pics! Get some realtime data here

[ChaseTruck754]

My point specifically here is that the geometry of the 64 kit is nowhere near the same as the spring over type configurations. A lot of the spring packs mentioned here are being used with stock brackets and mounting locations. Having had more than a little firsthand experience with the giant setup I will say that I do not think a 2 link or upper wishbone is feasible, at least not if using the maximum amount of movement the springs are capable of. 21-22in of travel is actually quite a difference from the 16-17 that a lot of bronco owners get especially when some of that 16-17 is in negative arch and over 60% of that movement is also droop. If any of you guys were able to just set a g70 gen 2 pack next to a standard spring over pack you will see there is no comparison they are completely different. So, just because the 2 links supposedly work well with the spring over packs doesn't mean the same would apply with the giant setup which is what the original post was about

You mean a pic like this?


The SO pack isn't a F53 or anything but rather a F87 or G7 (4-6" lift pack for Chevy) I think. I have both & can't remember which one I used in the pic. The big pack is a g70 gen 2 pack.

As far as far as 16-17" on F53s or similar - that seems like a lot! More than I'm getting out of that d70 pack for sure! Then again I refuse to let me springs go into negative arch & will not notch my frame unless the truck is fully cage - which mine is not yet.

Ive setup one of these 2 links before with j40 pack and there was binding. If people are using their setups and reporting added performance and no issues then their setup must be different than the one I setup or the spring packs work differently. Im not trying to dicount Autofab or Southwest in any way I know those two names are protected around here but I am reporting from personal experience from vehicles Ive built and driven.

I am all for anything that works well in the dirt. I also will add that on paper things are different that in real life function and I am in no way to proud to admit if I am wrong. Like I said ie neer messed with f53's before were it seems a lot of people on here have and it also seems that very few if any have any realtme expereince with the 64in kit.

Next time there's a meet at pismo we will have to run some broncos or do some ride swaps and get this figured out lol.

Not sure your accusation in red is correct...

[SteveG]

2-link question and Giant 64s 2 link question threads merged... I figured we'd keep all the 2-link discussion in one thread.


Kyle. the Autofab (and presumably the South west and Spirit) 2-link geometry is not perfect but it's about as good as that type of set up will get without adding a pivot between the leaf pack and axle.

I've posted this before but maybe it's worth repeating...
I like to see things for myself so I can understand how they work. So, when I installed the 2-link kit on my Bronco I broke the leaves down, added a block to take up the space of the leaves removed and cycled the suspension. To check the 2-link, I installed the 2-link kit but only bolted the front of the 2-link bar in. I cycled the suspension to full bump and full droop and a bunch of spots in between and compared the misalignment of the tabs on the axle tubes and the bolt hole in the 2-link bar. It was exactly as John said it would be. He said the geometry is really good in the middle 12" of travel then mis-aligns for the last few inches in either direction. Even with the misalignment, I could still get the bolt in at both extremes. The amount of misalignment was compensated for by the bushings.

Personally, I find this perfectly acceptable. Especially considering that most here agree that negative arc and not necessarily axle-wrap is what kills leaves on Broncos.

[cs_drums]

So from what I have gained is that 2 link is never gonna be perfect as far as binding. What about something like this-
Paint shop not CAD but you get the idea


This would mitigate the binding and still control the axle wrap. It would be a single link close to the center of the axle.
What do you guys think? I'd appreciate some feed back not bashing hahah

[philofab]

There would still be some binding as far as pinion angle. Nothing will ever be perfect but minimizing bind will maximize life of the springs.

I ran a single link on a spring under leaf setup that was off set about 10" from center to the right with great success back in the 90s. It did bind a little but never created problems.

[BDKW1]

2links by design will bind at a given amount of movement. im not a big fan of them at all and perfer an upper wishbone instead.

Having built and raced both, I can tell you for certain that a wishbone upper on leafs will bind the hell out of them on articulation.

A 2 link with bushings on the front will have some give and may bind a little at the extreme ends of the travel, but this is minor compared to what happens to the springs without them when you stomp on the go pedal.

The 7S ranger that We won the 06 B1K had a single bar off the top of the pumpkin with spring under. Big squishy bushing on the frame end and a hiem on the axle end. Loved that truck.........

[cs_drums]

Having built and raced both, I can tell you for certain that a wishbone upper on leafs will bind the hell out of them on articulation.

A 2 link with bushings on the front will have some give and may bind a little at the extreme ends of the travel, but this is minor compared to what happens to the springs without them when you stomp on the go pedal.

The 7S ranger that We won the 06 B1K had a single bar off the top of the pumpkin with spring under. Big squishy bushing on the frame end and a hiem on the axle end. Loved that truck.........

You talking about Doug's ranger that jd rebuilt?

Do you think its worth the extra heims and work or the shackled design?

What are we talking about as far as the little binding, 1/16", 1/8" etc.?

Here is the figuring i got so far its pretty primative, let me know if im in the right direction. Also is there a way to cycle the suspension with out taking the springs apart? I feel like they would react different with all the springs than with just the mains. I took a plum line and hung it from where the axle hits on bump. Then I dropped it out(21") and measured how far the axle swung forward(3.5"). I measured how far from bump I would like to ball park my pivot(6"). I transfered all the measurements to my bench and found 31" to be pretty close before my wife interupted haha

[MOSS2]

Probably want to measure change in axle /pinion angle through the travel as that will move where your mount is quite a bit in relation to the axle centerline. Otherwise plumb bob idea is good to determine fore and aft movement. ( unless you were measuring/plumbing always from the center of the link pivot bolt.)

[SteveG]

What are we talking about as far as the little binding, 1/16", 1/8" etc.?

Look up a few posts. We just covered that.

[cs_drums]

Probably want to measure change in axle /pinion angle through the travel as that will move where your mount is quite a bit in relation to the axle centerline. Otherwise plumb bob idea is good to determine fore and aft movement. ( unless you were measuring/plumbing always from the center of the link pivot bolt.)

I measured the pinion change from ride height to droop and it's about 5 degrees. Ride height is at 11" from bump so it's a out 50/50 bump droop from ride hieght. The closer he axle pivot is to the axle he less relevant the degree of change is correct?

[MOSS2]

If your mount is 2" above a 3" axle tube for every 5 degrees of rotation that moves your mount about .3 inches. Quite a bit. The center of the axle probably isnt the rotation point either its probably closer to the spring pad. Also not sure if you are still looking at the design illustrated above with the shackle but that I think would force the axle to rotate about 40 degrees through its travel. Just sayin measure lots before cutting and welding.

[philofab]

Ideally with a double cardan joint you want to keep the pinion and drive shaft almost parallel to each other. You need about 1 degree of difference so the u-joint caps rotate enough to stay lubricated.