sn0border88's SAS Thread

[IZwack]

Couldn't you just put a bump stop or something at the chassis to stop the shackle from rotating too far backwards?

 

['97 V8]

HOLY $HIT. Couldnt you just redesign the suspension. Move the shackle to the rear and solid mount the front.

 

[sn0border88]

IZ: I thought of that, and it would work BUT I still have the problem of axle wrap. The link solves both problems. If I did add a stop for the shackle I would need to add longer spring perches

98: Couldnt you just redesign the front suspension? Ummm.... I could. But there are easier ways, and then id need to shange my shock mounts, bumpstops, limit straps, everything. I dont want to do another SAS

 

[redranger4.0]

Axle wrap has alot to do with the springs you are using, if you moved to a leaf pack with more leafs but still retained the current spring rate, it would prolly help alot.

 

[IZwack]

I have no idea what I'm talking about but are you sure you have that much axle wrap at the front? Cauz isnt axle wrap typically the cause of too much traction and too much torque coming down the driveshaft? If so, technically you would only get that much traction when the vehicle is nosed down so that theres plenty of weight on the front tires to provide that much traction. I guess what I'm saying is that the axle-wrap bar makes sense on the rear cauz almost all of the weight is on the rear axle when climbing, but will it help much at the front?

 

[sn0border88]

They were watching as my pinion broke, and say they saw it coming. The diff wrapped down and held for a second or so, but I was on the gas a little to much and it hopped and presto.

 

[IZwack]

Oh wheel hops - gotcha.

 

[Mud Bug 94]

get the springs military wrapped...

 

[sn0border88]

http://www.fullsizebronco.com/forum/showthread.php?t=93378

problem solved, I think.

How do I go about calculating the length of the link, I dont think a reg 4 link calc will work for this application/

 

[IZwack]

I think as long as the link is as long as half of the leaf spring, then you should be good cauz its length is not fixed due to the shackle. I'm not sure using a 4-link calculator will give you anything also cauz such a link doesnt do anything with anti-dive or roll centers.

I like this one -- looks like the one I think redRanger posted:

I think the above implementation is better than the one below because the link's pivot point is at about the same location as the leaf spring's frame hanger

 

[sn0border88]

thanks IZ, I notice both of them are rear axles however.

Do you think the spacing of the 2 heims on the axle side is very important? I see the guy from FSB said 8" from center to center, and ovbiously the farther apart the more leverage you get for controlling wrap but since wrap isnt the biggest problem here I think I could keep them closer in hopes of having clearnce of the engine xmember.

 

[Mud Bug 94]

the pivit point wont matter if it has a shackle...if you put one w/o a shackle (i like better),it HAS t pivit even with the spring...

 

[IZwack]

Do you think the spacing of the 2 heims on the axle side is very important? I see the guy from FSB said 8" from center to center, and ovbiously the farther apart the more leverage you get for controlling wrap but since wrap isnt the biggest problem here I think I could keep them closer in hopes of having clearnce of the engine xmember.

Yeah you can keep them closer but flex the suspension and see what your limits are. I'm going to suggest you dont use heims on the axle end because heim joints just dont stand up to the average rig -- they're fine for competition rigs where they can be replaced after every few runs but they die quickly in mud and dirt. I ran a cheap heim on the panhard and it became "loose" in no time. I replaced it with a higher quality heim but I still worry about it. You can use the heim on the frame side of the link (where its a little higher) but if you can, use something that is rebuildable like a Rubicon SuperFlex, a "johnny joint", or the likes.

 

[Mud Bug 94]

all you need is to set it up like a 3 link like Mr.obama here....but insted of lower links you have leaf sprigs...kinda like a track bar that goes front to rear not left to right....follow me here?

just go to a local Tractor Supply and get a third link bar for a 3 point hitch on a tractor...make mounts and ur set...

 

[zainyD]

Another idea would be to shorten your front shackle a bit. They're pretty long right now. I have a feeling that it would be less likely to fold under plus even if it did you would be less likely to bend a leaf.

 

[redranger4.0]

all you need is to set it up like a 3 link like Mr.obama here....but insted of lower links you have leaf sprigs...kinda like a track bar that goes front to rear not left to right....follow me here?

just go to a local Tractor Supply and get a third link bar for a 3 point hitch on a tractor...make mounts and ur set...

This will not work, it will bind, A 3 link moves in an arc. the arc created by leafs is different, that setup will bind as it moves through the travel.

 

[redranger4.0]

I think as long as the link is as long as half of the leaf spring, then you should be good cauz its length is not fixed due to the shackle. I'm not sure using a 4-link calculator will give you anything also cauz such a link doesnt do anything with anti-dive or roll centers.

I like this one -- looks like the one I think redRanger posted:

I think the above implementation is better than the one below because the link's pivot point is at about the same location as the leaf spring's frame hanger

The shackle is what allows you to not have to mount it at the same point as the leaf spring end.

 

[sn0border88]

http://www.diy4x.com/images/antiwrap bracket.JPG

Ive decided to use that anti wrap bracket instead of making my own caus its only 20 bucks and im lazy.

Ive decided to go with evo heims based on a tech article from billvista. The evos are huge, first and foremost but also rebuildable, and have an adjustable shank so I can adjust pinion angle. Since they are so big and beefy they can withstand the stress any 3rd upper link will encounter counteracting axle wrap (my main problem) but they will also resist the force of the axle pushing back so whatever joint I put in there needs to be tough. A large RE joint may work, but I dont think it will offer the misalignment I need. Poly performace uniballs are a good choice but they dont seems like they will be able to handle the stress and I would still have to weld on a threaded shank so I can adjust them.

 

[james t]

What does your shackle angle look like with rig parked on level ground?

 

[redranger4.0]

http://www.diy4x.com/images/antiwrap bracket.JPG

Ive decided to use that anti wrap bracket instead of making my own caus its only 20 bucks and im lazy.

Ive decided to go with evo heims based on a tech article from billvista. The evos are huge, first and foremost but also rebuildable, and have an adjustable shank so I can adjust pinion angle. Since they are so big and beefy they can withstand the stress any 3rd upper link will encounter counteracting axle wrap (my main problem) but they will also resist the force of the axle pushing back so whatever joint I put in there needs to be tough. A large RE joint may work, but I dont think it will offer the misalignment I need. Poly performace uniballs are a good choice but they dont seems like they will be able to handle the stress and I would still have to weld on a threaded shank so I can adjust them.

Are you getting rid of leafs or just making a wrap bar? Cause a Large RE joint is more then enough misalignment. Im using RE joints on both ends of all my links for my 3 link. Save your money the Evo's are nice but are way more then you need to spend, for a wrap bar.