(TOM) Shackle Flip

[River Beast]

Lindel.... I will let you know....

As for the kits.... they will be reasonably priced I have to figure in my time and laber plus the cost of material AFTER I find a new supplier....


blt2crl,

Not a stupid Q at all.... I'll try top explain it.

The main reason for a shackle flip (in my eyes) was to compensate the 7" I gained from the SOA.. I HATE BLOCKS!!!

Just "flipping" the shackle as you described will not give you the amount of lift needed to "level" the FSJ back out. You can do this, but still need to fab a front mount so the spring will work properly and not at an angle of up and back.... up and down is how they are designed to work.

You can "flip" the shackle like you said... but remember to to fab a front mount to drop the front of the spring low enuf to level the the suspension... and this may not be enuf to sompensate for a SOA.


A little food for thought here:

If you were flip the shackle by cutting the bottom out...the total distance the spring moved is about 6" in the rear.... giving you a total of about 3" of lift AT THE CENTER OF THE SPRING (geometry works well on paper for a visual on this using inches here with ANY length of line)...not...BUT now you must "level the spring somewhat by fabbing a front mount of about 6" down to give the 3" in front needed to level the spring... thus giving you only 3" of total lift.... you would still need a 3" block to get your 6"

Why not just order a 4 spring 6" suspension system and SCREW BLOCKS!!!! you will be much happier... TRUST ME....

[ October 23, 2001: Message edited by: River Beast ]

[Iron Horse]

Hey RB,
I think what Blt2clr is asking is that he is looking for a way to compensate for the 2" blocks that the Rusy's 6" kit comes with. I have this kit also and I'll live with the blocks but....I'd like them to go away. We only need to get 2" at the rear axel (instead of the blocks) to match the 6" of lift at the front provided by the kit

If you *only* flipped the rear shackle and got 3" at the center, then the blocks could go, yes/no? But....what does this do to the pinion angle? Could you get enough correction wedges(?) to bring it back within spec.?

[ October 24, 2001: Message edited by: Iron Horse ]

[River Beast]

ahhhhh... "I see!!!", said the blind man.... I didn't know Rusty's 6" kit came with 2" blocks.

Now for this application... I believe what you both are trying to do will work...maybe... since you are not moving the shackle mounting point forward a good 1.25", it may want to pivot forward... this happened on my first attempt at this "flip"... and bind up after your suspension droops. HOWEVER... in regards to pinion angle, if Rusty's blocks are angle for pinion correction, when you lower the rear of the spring for the flip, and remove the block, the pinion will naturally be pointing more upward than before the flip and may be correct after all... but if not.... shims can be used. METAL shims not aluminum or plastic...

[Iron Horse]

RB,

So to be absolutely correct, you would need to remount the rear shackle support 1.5 " (or so) towards the front to keep it from reverting.

However.....
It looks to me if you cut the bottom out of the OEM box/bracket (remember this is an 80's wag) and weld on a new top plate, that the shackle is now "captured" (because of box type bracket)and unable to revert to it's original position. Whew...Does this make sense? This would *only* work for those that have the box type shackle mount.(?)

BTW, if I remember, the Rusty's blocks were NOT tapered. So what does this now do for the pinion angle? Just dbl. checking, but the pinion angle must match the t-case output angle, right?

Thanks,
Andy

[River Beast]

In respect to "capturing" the shackle... you are correct to a degree... but with lift springs, there is more arch to contend with, thus more pressure. Don't get me wrong...it might work. That's where you have to make the determination if you want to deal with mods you weren't planning on. It does give you a good sense of accomplishment when you finish...

As for angle...you should be ok.... and yes... the pinion angle and output angle should be within 1-2 degrees of each other to cancel vibes. A CV could be used if you can't get the angles just right.... that's when I point you to remember what I said before...you have to make the determination if you want to deal with mods you weren't planning on.

Nothing to it but to do it...jsut don't make any permanent changes that you can't reverse.

BTW... there is a small plate that is welded to the bottom side of the OEM shackle box, bracing it to the frame. This will have to be removed and somehow the box will have to be reenforced again to ensure rigidity.

When I fabbed my shackle mount, I removed this plate and made a new one that was part of my fabbed shackle mount and bolted it to the frame... worked out great...

[Iron Horse]

Thanks for the GREAT info and ideas RB. So now I'm thinking that if I fabbed a rear bracket like yours and corrected the pinion angle that I'd be in business. Cool!

Thanks,
Andy

[dennis w helt]

hey, i work in a sheet metal fab shop so i make lots of different brackets and such the brakets you need are eazy to fab a total of 10 minutes a piece so i can make them again i still have the patteren dennis

[graham]

Can someone please explain what "pinion angle" is? What has to be concidered when flipping shackles? Is it the angle of the universal joints in relation to the position of the diff and t-case?
I have done the rear shackle flip, keeping the front mount in its original position. No other mods have been done to allow for or compensate for pinion angle. As in these links.
Shackle Flip Page
Shackle Flip Pic

[Cecil14]

Pinion angle is the angle of your driveshaft to the yoke on your t-case or differential.

Hey RB, if you could I would love a set of drawings for those brackets and anything else needed for this mod to work. I'm going to do the SOA up front and would like to stay away from blocks. Also thought about getting some 4" rear springs and just raising stuff about 3" rather than 7". hehe

Thanks,
Anthony

[River Beast]

<BLOCKQUOTE>quote:</font><HR>Originally posted by Cecil14:
Hey RB, if you could I would love a set of drawings for those brackets and anything else needed for this mod to work. I'm going to do the SOA up front and would like to stay away from blocks. Also thought about getting some 4" rear springs and just raising stuff about 3" rather than 7". hehe

Thanks,
Anthony<HR></BLOCKQUOTE>

I think you are confused a little... the SOA gives you 6-7" REGARDLESS of springs... just as the rear shackle inversion will get you the same 6-7" REGARDLESS of springs...that's why you don't need blocks with this mod

[Cecil14]

RB - ok, think I got that now. What I mean though is that an option could be to get 4" rear springs and do something else in the rear to gain the additional 3" you would need to cover the SOA up in front.

Would still like to keep everything else open as an option though,

Thanks,
Anthony

[River Beast]

<BLOCKQUOTE>quote:</font><HR>Originally posted by Cecil14:
RB - ok, think I got that now. What I mean though is that an option could be to get 4" rear springs and do something else in the rear to gain the additional 3" you would need to cover the SOA up in front.

Would still like to keep everything else open as an option though,

Thanks,
Anthony<HR></BLOCKQUOTE>

Well...now that you have a 4" spring, you would need a 2-3" block to level it out tpo the SOA up front...or... mod the OEM shackel mont like described above to get 3"...but be careful. Taking the risk of doing this type of mode always turns into more than you bargained for...

[Cecil14]

<BLOCKQUOTE>quote:</font><HR>Originally posted by River Beast:


Well...now that you have a 4" spring, you would need a 2-3" block to level it out tpo the SOA up front...or... mod the OEM shackel mont like described above to get 3"...but be careful. Taking the risk of doing this type of mode always turns into more than you bargained for... <HR></BLOCKQUOTE>

Of course it is! It wouldn't be any fun if it went exactly as planned. I would like to stay away from blocks whatever I do and I figured it would be easier to make a 3" mod versus a 7" mod. Could be wrong though, that's why I'm here. hehe

Thanks,
Anthony