Shackle Angle

[JB]

This is just mocked up intot place. I am going to move the hangar up(to the left). But what would be a good unweighted shackle angle? 5 o'clock(30 degrees)?

[fbronco86]

its kinda hard to say. i think i set mine so that it was vert when nothing was on it. and mine turned out ok. you want it angled back when there is weight on it.

also i would like to steal those rear brackets from you.

[eight]

Your springs are pretty flat as they sit with no weight on em yes?

[Doug Krebs]

Ryan has a good point, if they are flat you'd want to make it so the shackle can droop more.

[aggiemudman]

are you using a rear hanger and shackle for the front? how much lift does this give you?

[Doug Krebs]

Holy crap!! I just noticed that was the front!! That is going to give you a HUGE lift, right?

[eight]

Why the 2 leaf super axle wrap special springs? They do it pretty bad even with stock tires on F-350s. I'd drop em in favor of some 3" wide F-150 springs.

I'm gonna guestimate that the springs are about 3" arched now, and will sit with 0-1" arch in em. Flattening 2-3" when they're almost flat allready and pretty long ain't gonna much change the shackle angle. So build a little more angle into it cause they'll be sitting at about their max angle at ride height, and the angle will lessen at both stuff and droop. I'd move the hanger forward at least 1" and try that. My front shackles sit at about 30* and my springs are nearly flat, less than 1" arch. It works great.

[JB]

I am guessing that I will get about 5-6 inches in the front with these springs.

Yeah are not very arched springs.

I was really only using them to get the rear hangars bolted into place and then eventualy bolt up a custom set of springs. Are you saying that the shackle angle would change withe different springs?

Mike, there a 1-2 pairs of those hangars at Hwy 6 junkyard, but they are a pita to get off with all hte rivets, even with the torch. It took the mexican about 2 hrs to get them off.

[eight]

It's just that you need to put the shackle at the right angle for where it will cycle. If you have arched springs and plan to get a lot of compression out of them, you can't angle the shackle as much as the springs get a lot longer when they compress.

When you use flat springs the springs are almost their longest at ride height, so when they compress they get a slight bit longer untill they go into negative arch and they will get shorter then, and of course when they droop they get shorter.

So you can set the shackle angle pretty far with flat springs because the angle hardly gets any greater. With arched springs the angle at ride height can't be a whole lot because the angle will change a lot when flexing.

Why do you want a large shackle angle? The suspension can only droop untill the shackle is in line with the spring, the greater the shackle angle, the further the suspension can droop untill this happens. Also makes the shackles less likely to invert.

[JB]

I had planned at setting it at about 30degrees. That is not that large is it? Then when newer flexier springs find their way under the truck, then IF teh angle needs a little adjusting, I can drill a new hole in the hangar either further left or right.

[eight]

30* is pretty large compared to most people's, but it's right for flat springs I think. Even with flexier springs I don't think you'll have to move it.

[aggiemudman]

what do yall think of my idea? Ive always wondered if i built a new front spring hanger that is taller if that would be ok for the drive angle and whatnot.

[Violentv8toy]

Originally posted by aggiemudman
what do yall think of my idea? Ive always wondered if i built a new front spring hanger that is taller if that would be ok for the drive angle and whatnot.

Just make sure it isnt so big that it screws up your castor.