LBZ: Rear shock angle?
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LOL. just seemed a lil weird & im convinced I have minor ocd when it comes to symmetry. Just seemed like they'd be more effective with jounce & rebound if they were vertical.
Yeah, the factory mount is not straight up and down. I suspect the angle actually helps with the suspension somehow, but I don't know enough about suspension to know for sure.
it doesnt, i would bet it was GMs way to use X shock on Y truck for Z price. angling in towards center makes a shock less effective than straight vertical.
For effective dampening, Yes. The further from vertical the less effective they are. OEM's and even various forms of motorsports utilize the shocks to help with other things (axle wrap..which is why the old GM's had one shock angled forward and one shock angled back), the other is to help with centering the axle (slight angle inward). I know on my pulling truck (front leaf spring suspension with no panhard bar), the front end would get a shimmy when it unloaded when I put my coilovers in a complete verticle position (removed factory shocks). An old timer told me to put them at a slight angle inward and the shimmy was gone COMPLETELY. I would have never believed it if I didn't experience it myself.
While the OEM's may do things to save a buck or two, they also have some pretty smart engineers who do certain things for a reason.....
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Shocks don't do squat for axle wrap in the sense your talking. Throw a gopro under a stock truck with a load in the back, hammer the throttle and tell me axle wrap is under control lol. There is a line between the best engineering of something, if it will physically fit and the actual cost to implement it. Money making business dictates that.
Your don't axle setup and leaning the shocks in is the same affect as adding a pan hard but does not work as well. When you run that low a leaf count, the leafs loose their strength to hold the axle straight. Soon as the bushing start to wear, you may feel the shimmy come back
Shocks don't eliminate axle wrap or even stop suspension bounce (that's not their design). The only thing they can (and are designed to do) is dampen it. Axle wrap will happen even with shocks installed the way several OEM's did it throughout the years, but shocks will dampen it from being as violent. Sorry if I gave the impression that putting them at a slight angle and/or mounting them forward and aft would give the same effect as a well designed four link, as they definitely will not (far from it), I was just stating that there is a reason why OEM's an others use them at angle other than straight verticle (where they dampen best).
Run an old school rig without shocks and see just how much more axle wrap (and extremely violent) you get. When I rebuilt my rig I did some "testing" without rear shocks installed and lets just say I'm glad nothing broke (not one of my smarter moves).
Also most leaf spring suspensions utilizing a shackle will travel in an arc so mounting them verticle would not be ideal anyway.
Understandable but I didn't say or imply shocks would eliminate axle wrap. I simply stated as you did before that they would not do a thing for axle wrap.
Running without shocks really isn't going to show you anything. All it's going to do is cause a very bouncy, unsafe ride as there is nothing there to control the UP and DOWN movement of the axle. How the axle then resonates twisting from that bounce is a spring issue. Shocks can't stop the twisting action of a axle from acceleration or deceleration unless they are valved so stiff the truck rides like a brick.
And the axle on a leaf spring won't travel I an arc, nor will the shocks. At no point do we want a leaf to go negative after being in a positive arc to flat. I've cycled the suspension of my old 7200 desert truck. It has 19" of vertical wheel travel in the rear with a 9" shackle. From full droop (max arc) to perfectly flat leafs, there was a perfectly linear line of the axle moving backwards 2" from full droop to flat leaf. No arc to it you could physically see or measure. A shackle will travel I an arc. A leaf will only grow outward on one end and the axle/shock will move up and back or down and forward in a linear rate.
Running without shocks really isn't going to show you anything. All it's going to do is cause a very bouncy, unsafe ride as there is nothing there to control the UP and DOWN movement of the axle. How the axle then resonates twisting from that bounce is a spring issue. Shocks can't stop the twisting action of a axle from acceleration or deceleration unless they are valved so stiff the truck rides like a brick.
And the axle on a leaf spring won't travel I an arc, nor will the shocks. At no point do we want a leaf to go negative after being in a positive arc to flat. I've cycled the suspension of my old 7200 desert truck. It has 19" of vertical wheel travel in the rear with a 9" shackle. From full droop (max arc) to perfectly flat leafs, there was a perfectly linear line of the axle moving backwards 2" from full droop to flat leaf. No arc to it you could physically see or measure. A shackle will travel I an arc. A leaf will only grow outward on one end and the axle/shock will move up and back or down and forward in a linear rate.
Correct, but due to the spring pack being connected to a shackle and fixed at one end, the centerpin does not move 100% straight up and down as the pack cycles. On an arched spring pack it makes more of a difference than a flatter pack. On a vehicle where the shackle is in the rear, the axle (and shock mount attached to it) will move toward the rear as the suspension is compressed (as you pointed out).
My only points are axles and shocks do NOT move in a straight line (up down forward and aft), and unlike you state shocks can and do help with axle wrap (never said it would control it).
If the OP wants to cut his brackets and make them verticle and pleasing visually for him, go for it. It will still dampen the suspension and most likely the little bit they are moved won't be noticed by the seat of the pants. There will be a difference though. It might be about as much difference (comparing apples and oranges I know but it for net comparison) as running 54PSI in the tires vs 55PSI. Will you notice it, probably not, but there is a difference.
Beyond that I'm not going to argue with you.