Front control arm flip

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The 80 already has a 30"+ long radius arm that has very little angle on a typical 4" lift, plus it offers virtually no droop as you prepare to climb an obstacle. This is why it is so easy to put the 80's front end up on just about anything as long as you can clear your approach angle.

Flipping the arms to help the 80 climb better re: the "wheelbarrow" example will have no practical advantage - in fact, adding flex to the system will create more droop on one side, which will cause the angle/leverage argument to come into play in certain situations. This is exactly what happens on Jeeps with very flexy long arm conversions - the tire still wants to push down and back when it drops into a hole and has to climb even with a 36" radius arm (a flat arm with a ton of droop will ultimately have more issues than a slightly angled arm that doesn't flex).

The price that is paid for this front end rigidity is of course rigidity as it's not terribly comfortable offroad, and it can force a lot of lean in some cases, but it will climb rather than pushing down pretty effortlessly. On an 80, this is not a problem that needs to be solved unless you are bringing significantly increased flex into the equation.

This is a good example showing what happens when you add flex to the front end - you get a tire in a hole, and it wants to push down and back even with a long radius arm suspension.

Now compare to the non-flexy 80. The tire doesn't drop into the hole (the whole rig leans into the hole, but the radius arm is keeping relatively little angle), so the front end climb is effortless, but because of the rigid front end it forces a lot of lean to take that line and the rear suspension has to take all of the flex. The 80 will feel much more tippy here, but leverage on the arm/wheel is not an issue whereas more flexy rigs really have to climb out of that hole against the natural tendency of the suspension.

"Flex" is never an independent variable, and it is not always in your favor on a large rig. Even if it makes for great poser pics on forklifts and curbs.


Nay a big solution for controlling flex on jeeps is the anti-rock bar..

Another awesome solution is the sway lock and is air actuated.
Welcome to Off Road Only!

It is a dual rate system... This means you can choose between a stiff and a soft swaybar ("Ant-Rock").

These guys are in MN. For the 80 and the front parallel 4 link I want to do I am thinking of getting some components of the system and fabbing the rest of the parts that need to be custom to fit.

http://www.offroadonly.com/docs/swayloc_install.pdf


They have an actuator which couples the inner and outer sway bar together on one side.

On the other side I want to be able to disconnect the inner bar from the arm with a second actuator. This will allow for Firm, soft and disconnected from the comfort of my seat.
 
Check out this online physics game. You can actually create little rigs that illustrate what is being discussed here. It's obviously rudimentary, but it can help you understand some of the concepts being discussed here if you are having a hard time visualizing it.

Fantastic Contraption: A fun online physics puzzle game
 
well, the more Ebag333 posts pictures the more convinced I am that we're on the wrong track. The arm is only a place holder, it maintains the axle's distance from the frame, that's it (well also locks it in for caster). The truck rests on the axle via the springs and flipping the arms doesn't alter that.

The ease of movement is determined by the direction of the force that's being applied to the tire and the course that the tire moves in response to that force. In his diagrams with the three arms there is no difference in the course that the axle takes. So any given force will result in identical results in all three cases.

Now if Ebag333 can draw another set of diagrams but this time lower the rear mount. You will see three distinct different courses that the axle will take and the one with the least amount of forward movement will be the most responsive one to forces being applied from that direction.

But all that isn't really the question at hand. It's whether or not if it flexes better which is to say that there is less binding in the bushings with an arm flip.

carry on
 
more flex is almost always better --the tire that unfortunatly falls in the hole in Nays example of the overly flexable jeep will be the same tire that stays on the rock and offers needed traction when a stiff 80 series lifts a tire.

flipping a rigid 80 series radius arm is such a waste of time. if one is to spend all the fab time to flip the arms they could almost as easily make a 3 link or make a jeep-like radius arm set up (which has a joint the the "y")

note that my 80 has radius arms in the rear that flex like mad.

THE OE 80 SERIES RADIUS ARMS SUCK ON THE ROCKS compared to almost every other solid axled rig out there. the 80's only saving grace is its lockers and wonderfull rear 5 link.

The easiest way to make the front end flex like mad is to make a better radius arm. you need a joint at the "y". do this and she will flex.
 
Dusty, your 80 has some serious articulation. Did you do a "Y" setup in the front? It looks like it is just a single control arm with one link on the axle end.
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After reading this entire thread I have reached a decision:


I am going to wax my truck.
















:lol:
 
anybody with 3-link/80 axle have problems i have thought alot about this and have wheeled with and seen dusty's flex like mad with his one tons....i have gone back and forth on which route to go, slee arms or 3 link i run 37" mtr's .anyone out have a report on long term use with 3-link/stock axle set-up, anybody have real life experience?
 
Besides my snorkel has a textured finish........................:eek:
 
F***ing sensors at work won't let me play:flipoff2:

That is probably a good thing. I have spent way to many hours playing that game during ethics lecture.


Dusty,

That makes sense now. I couldn't see that you had the 3rd link on top of the diff. Nice build thread, I had to force myself to stop reading it. D-60's seem to be the ticket but man that looks $$$$.
 
front is a 3 link.
rear is a radius arm with a joint at the "y"

pics of rear are in my build up

I don't see your point on the "y" link, your shock are just longer witch let the axle drop out, I would call that a bad idea with no control over your axle and loss of stability. Some times it's not all about flex.
 

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