Rear upper links mounted behind the axle

I don’t know enough about suspensions to know if that rear suspension setup is good or bad… if you got rid of the red accents and that lightbar there are a lot of expensive parts on that thing.
 
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The upper arms in back like that would force some odd packaging constraints to create desirable geometry. The control arm mounts on the truss are placed high for that reason to at least make the arms level to the frame to move the instant center forward some amount. I also see the opposing arms making big changes to the pinion as the suspension moves. I have no idea if this is a successful arrangement or not. But I don't see the point in doing it this way since it seems to result in a bunch of needless compromises to both geometry and up travel.
 
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It's a jk so a TJ style 4 link is a no go because of the JKs fuel tank. The opposing control arms cause the axle to stay centered in the wheel well during travel, instead of moving forward at full droop. The axle will rotate pinion up during droop, aiming the pinion at the transfer case, and rotate the pinion down at full compression. I've seen this setup before with a cantilever rear coil over. It looks like it has about 7-8 inches of up travel. eyeballing the length of the coilovers, and how much shaft is exposed, a lot of down travel. It's just solutions to problems. I don't know how it performs in the real world because I've never driven one.
 
I imagined the pinion would have some dive issues at the extreme ends of travel.

I’ve always wondered if links would work the same or could be made to perform as well if they were set up opposite of normal front and rear. I guess this answers half the question.

Weird packaging for sure. Looks like some of the decisions were made to ensure a full bolt on kit.

Owner claims 170k including 32k in labor to build.
 
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I dont know enough about suspension function and geometry to know if that's okay or the worst idea since the Yugo. I do know that's something I don't see often so they're must be a reason for that. Maybe somebody like @mrblaine who knows their pecker from control arm can educate us.
Seeing more clearly where the instant center lives would be the first thing to understand. Hopefully it is forward of the axle and not behind. And the more I think about it, the instant center is all over the place fore and aft of the axle as the suspension cycles. I don't know what that means. Though, my sense is that it isn't good.

On a JK, I believe the alternative to this is a rear 3 link with a track bar which would bring this closer to a traditional 4 link.
 
Rancho was the first to come out with that reverse triangulation not long after the JK was released and it did not live long.
 
Seeing more clearly where the instant center lives would be the first thing to understand. Hopefully it is forward of the axle and not behind. And the more I think about it, the instant center is all over the place fore and aft of the axle as the suspension cycles. I don't know what that means. Though, my sense is that it isn't good.

On a JK, I believe the alternative to this is a rear 3 link with a track bar which would bring this closer to a traditional 4 link.
I think Genright sells a tank that relocates behind the axle like TJs, then offers traditional 4-link options