Blue85 said:
I read your writeup and it's good. Nice job. I have a couple of questions, though:
1) Why does the shackle mount have to move? In your pictures it almost looked like the original position would have given an angle closer to stock. Is the concern that the shackle would invert?
with the shackle mount in the stock location, the shackles would be pretty close to vertical at normal ride height. This isn't a good thing. Think about how a shackle pivots/works as a suspension droops... it rotates about the upper bolt and the spring eye end moves forward/lower. This allows for a lot of droop. The other half of the equation is how far the spring will arch to allow droop. If you have a shackle that is straight up and down, as the suspension droops it hardly rotates at all, so the spring is left to do all the work. 52s are flexy springs, and I imagine (never tried it) that you'd get more droop than stock even with a crappy shackle angle... but with 52s and a shackle that "leans back" you'll get more. I haven't finished working out all the details on mine yet but I do know that I can compress the spring until its flat and the shackle/spring eye won't hit the frame. Thats what ya want.
2) Why do you have to move the axle, rework the steering, lengthen the driveshaft, etc? Can't this swap be done without moving the axle? Couldn't a zero-rate or a new hole in the spring pack and/or spring perch put the axle pretty close to the stock location?
Because the springs are longer, if you mount them the way I did, your front axle is relocated. To most people building trail rigs, this is a
good thing. By mounting the springs differently (ie moving the rear shackle hanger back) you could probably run 52s with no axle relocation at all. I wanted those 2", because I'm trying to clear 42s with 4.5" of lift + 1" of body lift + narrowing/cutting fenders. If you didn't want to relocate them, you could do it, you'd just have to relocate the hangers differently than I did. Also, whatever you do, don't redrill your spring packs to relocate an axle. Its just not a good idea, especially with an old used spring. Zero rates and offset-drilled perches are fine tho. I have used both. The latter is what I use on my rig now... its cheaper.
Steering doesn't really need to be "reworked" if you have x-over... I need to change my drag link length just a bit (like an inch) because the rockstomper one I have can't be shortened any more than it already is by adjusting the drag link ends. My tie rod needs to be shortened too, but thats because I am using WFO concepts steering arms, not cause of the swap.
driveshaft, as I mentioned, was always a little bit short for my app... I was trying to get my rig ready for BB one year, I didn't have everything put together so I had to guesstimate how long a shaft I'd need. I was short by a few inches... then I moved my front axle 3" forward (1" offset drilled perches + 52 swap)... and added mad droop. End result is that I need it lengthened some. It'd be fine for driving around on the street, but I'm pretty sure I can get it to come apart when I flex it.
anyway, thanks for posting the questions... helps complete my write-up.
j
