3" Drop Brackets for J-springs

[clownmidget]

Heath, regardless of our differences in opinion, that is really cool stuff and the kind of data that - at least for people like me - would better sell a product as being effective. It can't be that hard to model the behavior of the front axle on these with any and all of the possible mods available. Anyway, that is nice to see the way the two approaches work. Appreciate the post.

 

[LandCruiserPhil]

I wanted to make sure I was right about how the caster changes through the arc. Turns out I was not correct. I kicked one of our designers off his box and did a little dwg in AutoCAD, and the angle change seems to be the same for drop brackets or not. My bad. It is interesting though that caster plates move front to back 4 times as much as stock or drop bracket.

This drawing shows that if you have enough lift the front control arms on top of the axle would be ideal. And you can throw away drop bracket and caster plates.

You will always get some degree of bump steer on any lifted 80 because the the panhard and relay rod are different lengths.

 

[landtank]

Rick, maybe an update is in order.

Maybe another time.

 

[Walking Eagle]

Heath, regardless of our differences in opinion, that is really cool stuff and the kind of data that - at least for people like me - would better sell a product as being effective. It can't be that hard to model the behavior of the front axle on these with any and all of the possible mods available. Anyway, that is nice to see the way the two approaches work. Appreciate the post.

ya', a picture is worth a thousand words. Next time I'll start out with a picture and save myself the 1,000 words.

I'd love to have all the dimensions of the mounting points and control arms and model the mods. I could do the motion of the parts, but don't have anything advanced enough to do handling simulation.

 

[fj803fe]

ya', a picture is worth a thousand words. Next time I'll start out with a picture and save myself the 1,000 words.

I'd love to have all the dimensions of the mounting points and control arms and model the mods. I could do the motion of the parts, but don't have anything advanced enough to do handling simulation.

Simulation would be nice, as per your dwg, to note the axle "binding" occuring with the caster plates/bushings/axle bracket caster mods during axle articulation, that is much alleviated with drop bracketry.

MAJOR drawback....clearance loss with the drob brackets. If one has the necesary lift I think "flipping" the control arms should be a more standard correction.

 

[Walking Eagle]

Simulation would be nice, as per your dwg, to note the axle "binding" occuring with the caster plates/bushings/axle bracket caster mods during axle articulation, that is much alleviated with drop bracketry.

MAJOR drawback....clearance loss with the drob brackets. If one has the necesary lift I think "flipping" the control arms should be a more standard correction.

What is axle "binding"?

Flipping the control arms definately a great way to go, though the common rumor is that one needs at least 6" to do it. The coolest set-up on an 80 series axle I've seen was under a Amigo - heres the link http://www.houlster.com/amigo/SAS/

Over the top, and inside the frame rail - way cool

 

[clownmidget]

What is axle "binding"?

Flipping the control arms definately a great way to go, though the common rumor is that one needs at least 6" to do it. The coolest set-up on an 80 series axle I've seen was under a Amigo - heres the link http://www.houlster.com/amigo/SAS/

Over the top, and inside the frame rail - way cool

this is the "binding" that eventually stops your front axle from further articulation as long as you use two solid mounting points on the axle - regardless of under or over. That's why folks eventually go to 3-link or 4-link for more. This pic is of the stock brackets, stock control arms w/OME cc bushes. The upper right shows the metal-to-metal contact between control arm bush mount ring to axle bracket. It also shows the OME cc bushings don't necessarily give you "less" flex than the OEM rubber ones. They "might" be stiffer but under stress appear to eventually flex as much.

 

[landtank]

This pic is of the stock brackets, stock control arms w/OME cc bushes.

looks like one of those front adjustable mods on that bracket. The ones that use a mini truck ecentric cam to move the front of the axle up.

When you move the axle by pivoting the on the rear bolt you put a greater lateral movement on the front one. I'm not sure how much of what is shown is from that but I twisted my axle to a point where the rear tire was off the ground and the truck was teatering and didn't get that kind of twist in the front bushing. Maybe something where the 2 diagonal tire are lifted would do that.

 

[fj803fe]

What is axle "binding"?

After further thought, this could occur, but only to the extent that the pan-hard arm would bind within its brackets (call frame bracket point 'A', and Axle bracket point 'B') in a forward movement of A or B and corresponding aft movement of A or B-which in summation would not have a great affect in the possible rotational movement of the control arms duirng flex w/ a caster plate or bushing correction. And assuming the pan-hard arm (at this point) is perfectly rigid as well as all parts associated thereto.

Flipping the control arms definately a great way to go, though the common rumor is that one needs at least 6" to do it.

Hence...

If one has the necesary lift...

 

[clownmidget]

looks like one of those front adjustable mods on that bracket. The ones that use a mini truck ecentric cam to move the front of the axle up.

Well, Rick, you have me there kinda. The brackets are still stock, especially in terms of fxn in this context. Yes, I've got the ifs camber bolt/slot for caster adjustment but the pic still shows where it binds.

When you move the axle by pivoting the on the rear bolt you put a greater lateral movement on the front one. I'm not sure how much of what is shown is from that but I twisted my axle to a point where the rear tire was off the ground and the truck was teatering and didn't get that kind of twist in the front bushing. Maybe something where the 2 diagonal tire are lifted would do that.

That pic is with no shocks connected and panhard with Slee's threaded adjustable insert so it could rotate on it's axis. At that point the panhard is not binding in its bracket.

Granted you could force it a wee bit more such as when lifting the rear of the truck so all of its weight was compressing the opposite front wheel but not by much. That might just be structural movement anyway.

 

[landtank]

panhard with Slee's threaded adjustable insert so it could rotate on it's axis.

What item is this? I just ordered the DIY adjuster for the front but I thought there was a lock nut on it.

 

[clownmidget]

same one, just leave the locknut loose Seriously, once in hand you can see that it's design is different than that used on the upper rear control arms so that once it's installed it can rotate loose or tight, so I've just left the locknut finger tight. No issues since February and 20K miles...

What item is this? I just ordered the DIY adjuster for the front but I thought there was a lock nut on it.