Shackle hanger Oddity

I still think you would run into all the long shackle issues with that setup anyway but what do I know, I am not a mechanical engineer.

 

That notch they cut into the frame for the shackle end to fit up into looks like it would be dying to crack.

 

I notice on my 3.5" lift wrangler springs that the springs change so much in length when compressed that a longer shackle is required.

I kind of get the whole stability thing holding something from the top VS supporting it from underneath. I don't get it well enough to explain it.

Really an interesting set up. What is beyond the shackle that they notched it to keep the rest of that frame piece?

 

"Its still kinda street legal"

 

I'm guessing lower COG, there isn't room for a shackle the way it sits, but, they could have sleeved the frame for one. Doesn't look very stable does it?

 

Looks kinda scary to me but, I fear change. Seems like it could break off more easily than an underslung shackle hanger, especially on the landing from a jump. Don't really see any mechanical advantage. No hanger below the frame to catch on obstacles but, this guy is racing, not rock crawling. Longer shackle seems less stable to me.

 

I agree looks like it could just tear off the top.

 

To me it looks like they wanted/needed a longer shackle so their rear leaf springs could compress. You can see their leaf springs currently have alot of arch while sitting there. Those springs are probably able to compress alot after landing from a jump. A short shackle would not allow a leaf spring to compress without risking bending the main leaf near the mounting eye near the shackle. And, for the reason they mounted the shackle above the frame is to have better COG(center of gravity), this way the rear of the truck would not be lifted up so high, making the truck more stable during a jump.

 

My guess would be: more travel AND the longer the shackles, the flatter the arc (spring end stays flatter during full range of travel), more predictable???

I am going to mount my front springs (reversal) this way, but putting the upper mount bushing through the frame at the top, not on top of the frame!

Dale

 

i thought this might fit in this thread...
this jeep was on ebay, a built rock crawler. these rear shackles were used to extend the wheelbase in the rear. i actually like the idea a lot, and am considering something like this to extend my wheelbase. plus it allows you to mount them higher or lower in order to get the ride height where you want it. you can have them plenty long enough for any amount of flex/lengthening in the spring upon compression, then they would stop forward movement when they hit the bumper upon full droop (i guess that would be good instead of worrying about them moving too far forward and binding the spring?)
i like the idea, not sure if i'll run with it or not.

definately 'shackle hanger oddity'

 

that a diffinitly an odd one. judging by the shocks is got not much up and a lot down travel, and with flat springs they will get shorter with compression and droop. on compression, they will give in and not fight the spring, and shackle will hit the bumper and bind the spring on droop, poor man's limiting strap i guess.