need shackle help on a sas with 52'' springs

[outalne94z71]

ok suspension guys, heres what i got , i put 8'' lift 52''(overload leaf removed) rear bds chevy springs on the front of my 88 chevy pickup

i used the stock frame mount and swing shackle from the rear springs on an old late 70's early 80's 2wd chevy(turned upside down) and used stock 4wd 80's chevy front spring mounts for the front of the spring

now the problem im having is , when i put the truck weight on the front end, the swing shackle folds all the way back, i moved the front mount forward from the first attempt since the axle was too far back anyway, and it still would bottom out the shackle, now i moved the rear mount as far back as it would go(about 1 1/2inch back from the original mount point) and now the spring wont compress at all

should i move it back and use a longer swing shackle?, how do i compensate for the angle on the axle if i do that(has a stock degree shim on the spring pack already), i don't want to raise the front of the spring any more than it is, since it already looks like the front of the truck may be higher than the rear now(im not that concerned about it being a little high, the 350 is coming out and a heavier olds 455 and divorced 205 t-case are going in ,so it should go down)

the bds springs unloaded measure 49'' from center of eye to center of eye, should i put the mounts at 52'' on center? or should they be at whatever the measurement of a stock rear mount spacing on a 70's-80-s chevy with the 52's are at (keep in mind it would be like having a shackle flip for the rear since the swing hanger is now flipped being used for the front)


thanks for any help

 

[originalspanksta]

i would try the longer shackles first with the hangers where they are, those are some seriously tall springs!! Im in the midst of the same swap myself, but im using 1.5" lift 52's in the front(my hangers are 50" apart). right now its sitting on stock rear shackles, but i want to go a little longer. If you have the stock chackles on springs that tall, you may max out the shackle movement before the springs run out of travel.

edit: further thought, i hope you have a high pinion front axle with that much lift, or i pity you'r front driveline. i have a stock pass side drop chev 208 and a chevy 8 lug 10b front in mine and the stock front cv shaft wont work without grinding out the stops. as you have 7 more inches of lift that me (approx.) im not sure what you will do for a front shaft. (unless you run a divorced tcase, or clock yours down) i dunno, im rambling. lets get some more info on your build, so far you and i are the onlyones on here doing a late model SAS for wheeling. (unless you count willyswanter, but he's a bit ahead of us) follow the link in my sig and you can see my build in the IFS forum

 

[outalne94z71]

i already built 1 sas out of my 94 extended cab with the 47'' fronts, i have 10 inches of suspension lift (3 '' body also, so 13'' total)with that and a highpinion, the 88 3/4 ton that im building has a divorced t-case behind a shortshaft th400

this one originally started as a free 88 Ld 3/4 ton long box regular cab, i changed it to a short box which when moving the spring mounts on the frame and doing a shackle flip gave me about 14 inches of lift then i added a 3 inch block, the front well you know what springs im using there, as for an axle i want to use a chevy d60 since i already have the 5:13 gears for one, but if i can get a ford one i will go with that and run chevy outers, right now i just bolted a ford d44 up there just as a temporary thing to get things setup

depending on what d60 i go with i will use either a ford divorced 205 or a dodge one, in the rear i have a 14 bolt ff with 5:13's and a minispool, as for tires im running a set of 40x17x15 gumbo mudders that i cut, they will be good enouch for now untill the place i wheel changes the max size we can run, then i plan on 44's(this is the first year they put a restriction on tire size and decided to start at 40's, but will probably go up to 44's next season)

in this pic the 88 is still sitting low in the front, but with 28'' tires the box is at the same height as my 94 with the 40's on it

i saw the pictures in your buildup, i knew when i saw the first pictures with the springs that you had the front mount too far back, you need to move it so the hole furthest back on the hanger bolts into the 1/2'' hole at the very front of the frame , or as the spring compresses it will push the tire into the kick in the frame if you have the tires turned at all

i learned that real quick on my first build when i tried to run my brothers 38's