Flexing the 3 link
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Understated.
I'm three zip codes from a potential friendship with Garth Brooks, so understand completely.... 
Help me out here.
For this purpose, discussing the rear 5 link only.
Raising the panhard at the rear axle seems the acceptable manner to lessen the severity of the angle a lifted condition forces.
Can't raise the lower links above the axle (I understand they can be raised to the CL of the housing.) so the only means to return the lower link angle to a near OE angle is to move them further away from the axle housing, towards the front of the frame.
Before even considering link separation at the axle of frame, I realize there's all kinds of other data to process, but it would appear that, if maintaining the OE link separation at both the axle and frame, that lengthening the uppers and lowers, moving the frame side further forward, would correct all issues with the ass end walking around.
Add a JJ or heim to the equation (although I despise both) and this "fixes" the rear end, right?
I don't want the 5 1/4" rear lift I currently have, but without a coil over option, coil springs seem the only manner to suspend.
My mundane thinking is to literally move the frame mounts forward, to wherever they flatten out to an OE angle, raise the lowers to the CL of the axle housing, separate the uppers the same distance at OE at the axle housing, then replicate at the frame side.
Tell my why this thinking is in error?
The ass end of mine could wear yoga pants, as far as flexibility is concerned, so why does the wheel need to be reinvented, if the geometry of said wheel is still round?
Help me out here.
For this purpose, discussing the rear 5 link only.
Raising the panhard at the rear axle seems the acceptable manner to lessen the severity of the angle a lifted condition forces.
Can't raise the lower links above the axle (I understand they can be raised to the CL of the housing.) so the only means to return the lower link angle to a near OE angle is to move them further away from the axle housing, towards the front of the frame.
Before even considering link separation at the axle of frame, I realize there's all kinds of other data to process, but it would appear that, if maintaining the OE link separation at both the axle and frame, that lengthening the uppers and lowers, moving the frame side further forward, would correct all issues with the ass end walking around.
Add a JJ or heim to the equation (although I despise both) and this "fixes" the rear end, right?
I don't want the 5 1/4" rear lift I currently have, but without a coil over option, coil springs seem the only manner to suspend.
My mundane thinking is to literally move the frame mounts forward, to wherever they flatten out to an OE angle, raise the lowers to the CL of the axle housing, separate the uppers the same distance at OE at the axle housing, then replicate at the frame side.
Tell my why this thinking is in error?
The ass end of mine could wear yoga pants, as far as flexibility is concerned, so why does the wheel need to be reinvented, if the geometry of said wheel is still round?
Would it be possible to French the rear frame rails, or build a subframe that'd allow for COs to poke up inside the wheel well, requiring minimal sheet metal work to the wheel well and still retain the rear body mounts?
It'd move everything well outboard and be at an almost perpendicular angle to the axle, which I can't find any info claiming a bad idea.
It'd move everything well outboard and be at an almost perpendicular angle to the axle, which I can't find any info claiming a bad idea.
You said nothing wrong in the above post as far as i can see. However, replicating the stock geometry on a 4-5" lift would put the upper link @ axle thru the floor.
Triagulating the lowers is gonna yield the biggest punch, but we have gas tanks. A 1" bodylift would raise the gastank enough to get a decent frame connection for inboarded lower link frame mounts? They would need to be
An outrigger style like 4wu employs on his parts. A crossmember would land on the driveshaft.
A 40" link sitting right were the center hole is on the gas tank skid plate just behind the forward mounting strap would be ideal.
Triagulating the lowers is gonna yield the biggest punch, but we have gas tanks. A 1" bodylift would raise the gastank enough to get a decent frame connection for inboarded lower link frame mounts? They would need to be
An outrigger style like 4wu employs on his parts. A crossmember would land on the driveshaft.
A 40" link sitting right were the center hole is on the gas tank skid plate just behind the forward mounting strap would be ideal.
If you wanna move the shocks from where they sit on the axle you can resolve 90% of this by freeing up realestate for a lower link mount further out and up without as drastic changes at the frameside attachment.
I hope that makes sense?
I hope that makes sense?
There's really no way around a three link with pan hard on the rear end, as it poses the same real estate issues as the front.
That said, and for greater understanding, should the upper links triangulate (??) opposing?
If the rear upper runs from axle to PS, shouldn't the front run to DS?
Let's pretend that the lowers are moved to the axle CL, as previously discussed, with the single upper link be separated similarly and be as far forward, as the two uppers would've been ( if tank wasn't in th way) ?
Went through a similar round table discussion on the FJC, and it was decided the best way to address was to subframe both the center ( integrated link mounts with tranny/TC mounts) along with chopping the rear frame out, to send COs through a frenched rear frame rail, incorporate anti sway into the cross member. (Transverse, or "anti-rockish in Denglish)
The problem always came back to gargantuan lift heights due to WB.
I want to lower my 80 and the WBs don't differ greatly, so that'll be a concern to address at some point.
That said, and for greater understanding, should the upper links triangulate (??) opposing?
If the rear upper runs from axle to PS, shouldn't the front run to DS?
Let's pretend that the lowers are moved to the axle CL, as previously discussed, with the single upper link be separated similarly and be as far forward, as the two uppers would've been ( if tank wasn't in th way) ?
Went through a similar round table discussion on the FJC, and it was decided the best way to address was to subframe both the center ( integrated link mounts with tranny/TC mounts) along with chopping the rear frame out, to send COs through a frenched rear frame rail, incorporate anti sway into the cross member. (Transverse, or "anti-rockish in Denglish)
The problem always came back to gargantuan lift heights due to WB.
I want to lower my 80 and the WBs don't differ greatly, so that'll be a concern to address at some point.
Load up the 3 link calculator and use the numbers posted on page 18, but change axle end lower links Y number to 22.25 and Z to 18.
These are numbers than can 'easily' be obtained without major surgery, BUT require the removal of the factory shock mount.
These are numbers than can 'easily' be obtained without major surgery, BUT require the removal of the factory shock mount.
Where do the top of the shocks mount to? Do they angle inwards towards a crossmember between the frame rails? Can't be run into the wheelwell, where a hoop would be fitted. The top mount can sit higher then, so the lower shock mount can be on top of the lower link mount.
Pushing the lowers out as far as you can and on axle centreline, getting the frame mount inboarded by an inch or 2 if possible will massively lower RAA. It does reduce antisquat to 40ish percent. To raise that you could lower the top link frame mount by 1/2" to an inch. No idea how easy that is though, I don't know what those mounts look like...
Pushing the lowers out as far as you can and on axle centreline, getting the frame mount inboarded by an inch or 2 if possible will massively lower RAA. It does reduce antisquat to 40ish percent. To raise that you could lower the top link frame mount by 1/2" to an inch. No idea how easy that is though, I don't know what those mounts look like...
Something like this?
Here are the numbers as they were:
Here are the numbers as they were:
Awesome! Now add 5" to pan hard axle end Z coordinate.
40-70% AS in the REAR is a waterfall launching mutha fawker and very ideal for propulsion
Flattens the RAA a tad furhter 
Will dig out the "file" because there was a decent DWG produced that showed the frame rail modification, allowing for a shock tower that was the "cap" for the frenched frame rail.
Pretty much, directly above the axle CL, perpendicular to the axle, a 2.5" CO ran straight up, centered where the OE frame rail would be.
Would've required some sheet metal work to the inner fender, but minimal.
The one item I neglected to consider, when mentally comparing to the 80, was the increased D60 axle width that allowed for more clearance between tire and CO that wouldn't be afforded on the 80, but the concept still may bear more fruit than cantilever or progressive coils. I don't know.
Was contemplating on a cross town journey at 75mph and I friggin love how mine rides, in a straight line. You could never tell it was lifted and on Krawlers.
Take someone much smarter than myself to replicate with COs.
This scenario is entirely possible and reasonable considering the space constraints and available real estate on the 80 axle.
The upper link axle brackets will probably need some attention as they only sit 5.25" away from the lower links mounts now, but that is just a matter of some strategically placed material and improved connection to the axle housing.
The upper link axle brackets will probably need some attention as they only sit 5.25" away from the lower links mounts now, but that is just a matter of some strategically placed material and improved connection to the axle housing.
Flattens the RAA a tad furhter
This was my solution to factory 5link
pollution. I can't replicate this on an
80, But the guy who sells these brackets might?
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Basically just beefing them up. That's all that's needed, there's no particular reason separation should be a lot more if the upper mount is strong enough.
Yeah, looking at pics of severely rusty 80s from the northeast certainly poses the potential for disaster.
I think the owner of this website recently destroyed his non rusty upper links(not the mounts themselves) in
moab?
I think the owner of this website recently destroyed his non rusty upper links(not the mounts themselves) in
moab?
Pics worth twenty five gazillion words.
Dave and Newb's rear solution, loosely modeled off LTs 3 link "kit".
Only comparing due to striking similarities in the OE frame and link configuration and lengths.
Installed AP links on a local's a few weeks ago, and accidentally grabbed an OE 80 upper, to establish length.
It was the same, and the lowers are within a 1/2" OAL.
Dave and Newb's rear solution, loosely modeled off LTs 3 link "kit".
Only comparing due to striking similarities in the OE frame and link configuration and lengths.
Installed AP links on a local's a few weeks ago, and accidentally grabbed an OE 80 upper, to establish length.
It was the same, and the lowers are within a 1/2" OAL.
