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front shackle angle

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skyhigh4by

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I put 8" BDS front springs (47") under my 82 and also added the ORD shackles. The shackles are angled the wrong direction...towards the front. I know ideally they should be angled slightly backwards for optimal ride and thats what I would like. Its a daily driver/weekend warrior so I want to get best drivability possible. Is there anything I can do to correct this besides having to go to 52"s??

PS Im not expecting a caddy and I know lift springs are gonna ride hard. I just want to make the best of what Ive got.

Thanks Ryan
 
normal for lift springs .

first thing to ask in ride quality is what brand of shocks . ?

cheep shocks will make them ride like a dump truck .
 
sweetk30 said:
normal for lift springs .

first thing to ask in ride quality is what brand of shocks . ?

cheep shocks will make them ride like a dump truck .
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Bilstiens from ORD. Rear has DIY4X shackle flip. Rear seems pretty smooth. Can tell that the harshness is coming from the front. I wouldn't consider the ride horrible I just know that with correct shackle angle it could be better...
 
For those springs, the shackle angle should be slightly forward. It actually makes for a lower effective spring rate (softer). Don't believe everything you read on the internet :whistle:
 
38377k5 said:
For those springs, the shackle angle should be slightly forward. It actually makes for a lower effective spring rate (softer). Don't believe everything you read on the internet :whistle:
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Interesting. Thanks.

So basically your saying is that the springs soak up the bumps more than the shackles swinging their swing? haha

Is it something specific about these particular springs?
 
It has to do with how much the spring changes in length compared to the shackles actual direction of motion in its arc.

As the shackle swings in its arc its moving both horizontally and vertically.

In our chevys when the shackle begins to move, most of its motion is horizontal which allows the spring to flatten out with very little resistance other than the rate of the spring itself. As the shackle continues to move in its path the horizontal motion becomes less and the vertical motion becomes greater. In this area of the motion, the spring will begin to be limited on how much the length can increase due to the shackle now becoming the limiting factor.

Of course there are some other factors involved, such as shackle length and spring length, both flat and along the arc, placement of the shackle eye hanger etc. etc.

Personally, I like the angle to be angled just slightly rearward. Probably just a tad more forgiving in the overall setup.

Angled forward there always seems to be a bit of a "conflict." I don't think i'd call it bind. When the spring is trying to compress the shackle being angled forward actually needs to rotate downward just a touch. For that brief instant the two are working in opposite directions. It's probably so minor that it isn't worth dealing with. Just an OCD thing.

It would help to see some pictures of the truck in question. And on the same note, are the springs new? They will settle to some degree which will change the angle of the shackle as well. For now, i'd say the best thing to do is nothing.
 
38377k5 said:
For those springs, the shackle angle should be slightly forward. It actually makes for a lower effective spring rate (softer). Don't believe everything you read on the internet :whistle:
Click to expand...

Sorry I'll never by into that philosophy. My ass told me otherwise in every vehicle Ive ever set the shackle angle in. 20-30* back, best ride you can get. Im not trying to be disrespectful to you Chris and I know what your saying is what the book says on geometry and shackle angle but theres alot of us on here who feel this way.
 
Stomis said:
Sorry I'll never by into that philosophy. My ass told me otherwise in every vehicle Ive ever set the shackle angle in. 20-30* back, best ride you can get. Im not trying to be disrespectful to you Chris and I know what your saying is what the book says on geometry and shackle angle but theres alot of us on here who feel this way.
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Part of shackle angle depends on spring arch.

But the math doesn't lie, and because your butt dyno thought that they got softer doesn't mean that they did. It's physics :whistle:
 
38377k5 said:
Part of shackle angle depends on spring arch.

But the math doesn't lie, and because your butt dyno thought that they got softer doesn't mean that they did. It's physics :whistle:
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So your saying a flatter spring would be more beneficial to a set back shackle while a spring with a heavy arch will require a forward facing shackle?

As a note Ive NEVER had anything more than a stock spring be it 52s up front or a stocker in the back with a shackle flip.
 
Stomis said:
So your saying a flatter spring would be more beneficial to a set back shackle while a spring with a heavy arch will require a forward facing shackle?

As a note Ive NEVER had anything more than a stock spring be it 52s up front or a stocker in the back with a shackle flip.
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With a flat spring, as it goes inverted (which is actually fine as long as it's within the design of the spring), an angled shackle actually makes the spring rate stiffer.

With, say a 25 degree angle on the shackle, as the spring compresses, it has to bend the tail of the spring downward for the shackle to swing forward and that increases the effective spring rate. It depends on the spring, but putting positive angle on the shackle with a flat spring makes the rate higher, and that's a fact.
 
Depending on all the factors... Stomis, your butt dyno may be accurate.

EDIT: and now that I think about that statement, that is all that really matters.
 
Shock has a ton to do with this as well, if your valving is off all things being equal it will ride like crap. My blazer rides decent and it's shackle in in the stock location.
 
Heres a few pics just to stir the pot. Truck isn't sitting on perfectly flat ground but close enough to get the idea. The springs are new BDS 8", shocks are new bilstien 5125. I never said that the truck rides poorly. It is a little bit harsh in some stuff but I think its expected to some extent. I only brought this up because to me it seems as if the spring and shackle would be working against each other until the shackle was at least vertical or a little bit angled toward the back.

http://s41.photobucket.com/user/Rus...kles/IMG_0184_zps2c309644.jpg.html?sort=3&o=0
 
I'll stay with my previous recommendation and suggest holding off for a while till the springs settle in a bit.

If things don't change enough to suit your driving conditions/style etc. The simplest solution would be to move the shackle eye hanger forward slightly.

Hanging 52's is kind of a leap from where you are now. Just not necessary.
 
cybrfire said:
I'll stay with my previous recommendation and suggest holding off for a while till the springs settle in a bit.

If things don't change enough to suit your driving conditions/style etc. The simplest solution would be to move the shackle eye hanger forward slightly.

Hanging 52's is kind of a leap from where you are now. Just not necessary.
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That was my first thought too I just wasn't sure if moving it just a little bit was recommended. I would love to swap in 52s but my truck has a double life and needs good predictable road manners (which it mostly has right now)
 
I agree with Kert on letting the springs settle first, and to be honest, I expected the angle to be worse then what it is, doesn't look that bad.
 
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