Rear shackle angle

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Charlie Kleman

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Got my 14 bolt underneath the blazer yesterday. I’m running 56” springs in the rear and using an ORD shackle flip kit. In my laziness I tried mounting the brackets backwards to see how the shackle angle looked vs drilling new holes. By flipping the brackets side to side i figured its not that far off from moving them back 4” on the correct side. I know there’s many variables that go into shackle angle just wondering what anyone’s thoughts were on this.
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nvrenuf

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I’m no suspension expert but it looks ok to me. I’m running 56’s w/ ORD 2.5” shackle flips (swap sides like you) and my shackle angle is similar. My set up hasn’t shown any issues and works well.

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Charlie Kleman

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Thanks! I didn’t think it looked too bad but I wanted someone else to say it too haha
 

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So now when the spring compresses the shackle moves forward. In doing so, it's gonna lift the truck because of the pivot point location. Will it matter? Not if you don't know any better.
 

bucket

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Looks pretty good to me. That angle is about what I would shoot for personally.

Also, swapping them side to side ain't lazy... it's simply doing things the right way :)
 

bucket

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So now when the spring compresses the shackle moves forward. In doing so, it's gonna lift the truck because of the pivot point location. Will it matter? Not if you don't know any better.

Say what now?

When the spring compresses, it will move the shackle to a more horizontal position, not vertical.
 

SquareRoot

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Say what now?

When the spring compresses, it will move the shackle to a more horizontal position, not vertical.
Lol. I was just looking at the photos again and I agree because of the springs arch. I went thru something similar on my D60 on the front but it had flat springs and bends the other way. My bad.
 

ali_c20

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Looks good to me. Smart to swap sides and use existig holes in the frame.
 

89GMCJimmy

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Would you want it to be angled back as opposed to 90°
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89GMCJimmy

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Does the shackle flip require that
I was told the stock shackle should be as close to 90° as possible.
 

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Would you want it to be angled back as opposed to 90°
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Your angle seems to be fine as well. Tension shackle works a bit different than the compression shackle shown above.
 

Blazerbiker

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It's too steep. Or rather, it's less than optimum. The feel you'll get it that the spring will get really stiff when it goes flat. These trucks can and will have a couple inches of travel in reverse arch and a really steep shackle angle robs you of that travel. We've played with this and you can make the suspension lock out when the spring is flat where a less severe shackle angle will let it move into a reverse arch freely. The overload starts adding a bunch of rate when the spring goes flat and when you combine it with some shackled "binding" it gets way worse.

The effect is from the spring needing to pull the spring eyes closer together as it compresses past flat. As this happens, the shackle has to stand up and the longer the shackle is and the more laid down it is, the more you're picking up the truck to make this happen. This translates to skyrocketing spring rates which make the movement not happen.

What you have "doesn't not work" but it can be better. Giving up compression travel past flat is OK when your spring is done working when it's flat like one of our 4" lift tension shackle rear springs with 12" of arch but you're not in that situation.
 

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