moving your leaf srping underneath the frame rail!

Long and lots of pics - so shoot me!

ashmanjeepxj said:
I wana see some more pics matt!!

Im not a fan of moving the perches in-board.
Stability was brought up, and I agree, it would be soft, flexy but not stable.

Matt, this is my 3/4elip plan.. Ill be running my d70 rear with the perches welded to the factory cherokee leaf perch width.

I will use a factory Xj no lift leaf back for the 1/2 elip adn use two leafs out of an F350 pack I have for the top 1/4elip.

I will flip the XJ pack so the longside goes to the front. I dont want to stretch my wheel base that much so Ill make new mounts further forward then stock.

I plan to get 8.5in of lift from the shackle and the f350 leafs.
I want the upper 1/4elip to not be fully compressed at ride height.
Have a fixed frame end mount like yours to limit the down travel unlike the double shackles.

yours looks like the top single leaf 1/4elip has no up travel compression.

what do you think?

Yes I know my described set up will cuase some big anti squat due to the angle on the lower 1/2elip but I have the stuff and want to give it a try. Ill later on build a link set up to fix the anti-squat and eventually replace the "free" leafs with some coilovers..

I have a 2dr and will severly trim instead of increasing the wheel base. I have some skinny bucket seats to replace the back seat so I can extend my wheel wells forward to where the bench used to go. Gas tank I want to move up anyways.

for now just fitting 37s and keeping it full width.

What do you think of my 3/4elip plan?

I see two issues - the frame is not very thick at all where I mounted the buggy leaf - this is fine because it really only sees the loading of the YJ mainleaf's (buggy leaf) spring rate - when at ride height the shackle rests on the underside of the frame plated with 1/8" - a f-350 pack will load the entire weight of the vehicles rear end onto that point in the frame...

This leads to number two that area of the frame rail is very difficult to reinforce so it could handle those loads - if you were to do this I would just go quarter elip in the back for all the work its going to take.

Do you have a reason for not wanting to go with a simple single buggy leaf?

Borton has nicely done the spring flop and really only had issues with the gas tank - however if you move the main eye foward that would be solved...

Here are some pics of both the frame mount and the buggy in action...

buggyup1.jpg


buggydown2.jpg


ramp4.jpg


rear2.jpg


anti_wrap_bar1.JPG


Last one I promise! - shows the height of the brackets and for all you long arm haters you can see the 3-link crossmember mounted along with the RE drop brackets - Matt
xmember1.jpg
 
I'm with the naysayers on this one, I don't think it's a very good idea. The negatives are loss of stability and loss of ground clearance. Flex just isn't much of an an issue any more. It's very easy to get good flex with what is already commonly known, and it's been demonstrated over and over again that too much flex, and it's resulting lack of stability, actually hurts trail performance. Like Ed already said, Bill Ansell tried this and didn't like it at all, and went back to the stock location.

The other thing that hurts trail performance is less ground clearance. We're all figuring out how to keep things tucked tight up inside the frame rails, like using high clearance cross members and slid plates. We already drag the whole frame over rocks, and scrape the bottom of the stock spring hangers, so moving the spring hangers below the frame would just make it worse. anyone who says this isn't, or wouldn't, be a problem just hasn't done much rock crawling. If you run mud, then who cares, but then why would you need more flex, and why would you want less stability?

The proof is in trail performance......... :confused:
 
My experiance with stability...

SyCo said:
Matt, where did you get those spring perches and how much were they if you don't mind me asking?

They are home built - cost ~3.50$ each :D

I would agree with both Goatman and Crash if it were not for one thing...

When I ran the OEM 5 link up front is was very floppy and had terrible manners (worked great on the trail but that was about it) I then went to the 3-link I use now and the whole rig became much more stable - both front and rear - I can't explain why but the difference was night and day - I think it has some to do with the changes I made to the roll axis at either end...

In that picture of the jeep on the ramp that is a 30 degree ramp and the rear tire is still firmly planted on the ground; I cant even rock the jeep...

What both of you say makes sense its just my experience that mine is different - luck perhaps...

Ed S. I agree completely - I rarely touch those hangers and when I do I am scrapping my diff and or axle tube on the same item... I hit the frame on my rig once in a blue moon so I have not fixed them since they are working for me :rolleyes: Just my 2 ct's

Matt
 
Goatman said:
(snip).....Like Ed already said, Bill Ansell tried this and didn't like it at all, and went back to the stock location....(snip)
I can appreciate the concerns regarding possible instability, but it's difficult to use Bill's setup as an example of what should and shouldn't work. If anyone remembers seeing photos of his leaf pack...way-past-worn-out leaves that reverse cambered while the Jeep was sitting on flat ground, shocks that were also past their due date and mounted very close together at the top.
 
Re: Long and lots of pics - so shoot me!

Matt said:
I see two issues - the frame is not very thick at all where I mounted the buggy leaf - this is fine because it really only sees the loading of the YJ mainleaf's (buggy leaf) spring rate - when at ride height the shackle rests on the underside of the frame plated with 1/8" - a f-350 pack will load the entire weight of the vehicles rear end onto that point in the frame...

This leads to number two that area of the frame rail is very difficult to reinforce so it could handle those loads - if you were to do this I would just go quarter elip in the back for all the work its going to take.

Do you have a reason for not wanting to go with a simple single buggy leaf?

I wanted to go buggy leaf for now cuase I didnt want to build links for the rear yet...

Yea yea, the 1/4 elip would be better with well designed links...

I just want to get my 1tons under the jeep fast and have the stuff to do the 3/4eilp in the garage..

Other wise Ill have to save up for 8 spherical bearings or johney joints $$$, some threaded weld-n-inserts $, and some tube $$...

Maby I should just do the tirangulated 4 link I want now, and not even bother with the 3/4 elip idea...

Yea maby I should just wait.. its only been a year collecting parts so far...

The susupension joints are the High cost.. RE jonny joints $38 each or so, or get the BIG spherical bearings 1.25in $50each.

Then $12 each of the threaded inserts...

3/4 elip free, free... some scrap metal, welding time..

I dont know, talk me into something...
 
Go the whole 9 yards and do the quarter elip - you will thank yourself later with the tuning options and the wrap control...

That is the other bit I forgot - do not even try to do a buggy with out making a traction bar (add one more heim into the mix and you have just used as many as would be needed for a four link...)

The links will give you alot more ability to grow and tinker if you go to something else - say, coilovers :rolleyes: later on...

Your right just wait a little while longer (eat some ramen) and do it the correct way, HTH

Matt
 
Matt said:
Go the whole 9 yards and do the quarter elip - you will thank yourself later with the tuning options and the wrap control...

That is the other bit I forgot - do not even try to do a buggy with out making a traction bar (add one more heim into the mix and you have just used as many as would be needed for a four link...)

The links will give you alot more ability to grow and tinker if you go to something else - say, coilovers :rolleyes: later on...

Your right just wait a little while longer (eat some ramen) and do it the correct way, HTH

Matt

Why 1/4 and 4link and not 3/4 elip and 4link?

I will only consider a 1/4 elip with a fixed frame mount not a hinged "no controlled drop" type 1/4 elip.

Im thinking if I run the same 1/4elip for the upper part of the 3/4 eilp it would have more wheel travel then just the same top 1/4 eilp section fixed to the frame...

you said it would be difficult to make a 3/4 elip out side the frame, but if I did a fixed 1/4 eilp I would also mount it out side the frame for added stability, so it wouldent be much harder to just do the 3/4 elip.

ground clearance, that has been brought up afew times on this thread.. woudl be ALOT better on the 1/4 elip set up,

and like you said the 1/4 elip woudl be more eaisly adjustable. jsut change the shackle length at the frame end for more height... on the 3/4 eilp any more shackle will decrease ground clearance...

I should just do what all the comp buggies do.. a 1/4 elip
:rolleyes:

Id also want two more jonny joints for the alxe ends of the shacle mounts on a 1/4 elip. That will save the main leaf form twisting.

Im almost decided to do 1/4 elip, now to decide under frame or out board of the frame?
 
Outboard...

I just got some f-550 spring packs for the 1/4 ellip in my willys - I am going to use the whole pack and mount them inverted with the shackle end on the axle and the main eye on the frame - there will be two hydraulic rams (one each side) attached to spring clamp/ center pin area for ride height and off-camber control :rolleyes: I figure what ever I build has to be complex so why not run with it... ;)

Matt
 
Matt said:
Outboard...

I just got some f-550 spring packs for the 1/4 ellip in my willys - I am going to use the whole pack and mount them inverted with the shackle end on the axle and the main eye on the frame - there will be two hydraulic rams (one each side) attached to spring clamp/ center pin area for ride height and off-camber control :rolleyes: I figure what ever I build has to be complex so why not run with it... ;)

Matt

Thats cool.. My runaway project mind has also thought about doing hydrolic rams...

Theres always somethign cooler to try...

:eek: Im getting tired I need a vacation..:fuse:
 
Yup that rig was/is pretty darn cool but I had thought for along time about a little 4 cyl diesel and big hydro pump for a completely hydro rig - fluid motors at the wheels and an independant suspension like this guy did...

Major props for building it; no matter if it catches fire and explodes the second time out - got that much farther than the ideas floatin around in our heads :rolleyes:

Matt

I am still toying with the idea of a long hydro cylinder with some quick connects so I could use it like a highlift :D
 
ok now i am still trying to figure out this ground clearance issue!! so i drew this quick little picture!!
framerail.jpg

i know it is bad!

No matter where u mount the leaf spring mounts the ground clearance will depend on the hight of the tires and the leafs springs! if u make mounts 10 inches lower and if u have 10 inch leaf srping the ground clearance will still be the same as if 10 inch leaf springs with stock mounts!

just trying to firgure out ur guy's logic here????

stoney
 
I think crash was comparing across standard frame to ground distances - but the way mine is set up is like your drawing - the brackets provide some of the lift... Likely why I do not scrape my frame as often others is the fact that although my leaf spring is pretty flat the frame is a fair distance from the mounts... I think it comes down to personal preferance and experiance...

As tire size increases you get more tire towards the edges of the spring and shackle hangers and even though the mounts hang below the frame the tires begin lifting that portion of the frame sooner so it does not contact the offending object...

My 3ct's: if you run 38's and 7"+ lift you should not be all over your frame - unless you drive like an idiot :rolleyes:

Matt

PS Stoney - my appologies for the severe highjacking we just finished up!
 
Well, I don't think anyone doubts that I do serious rockcrawling regularly. I say that to put a little experience into my comments. When you are scraping over a rock or ledge, it matters little what amount of lift you have. The tires drop out if the frame is on a rock, so whether you have 5" of lift or 8" of lift only means how much your tires are drooped at the time.

Sure, you're drawing is correct, and so is your thought process, but only when you're sitting still, not when you're in a boulder field. You may only get hung up every now and then, depending on what type of trails you want to run, but when you do those around you will point at your lower spring hangers and get a kick out of ribbing you about it. One thing about these forums, unless you know the person who is making the comments, you never know how much real world experinece is behind the knowledge or opinions that are given. Wheeling in rocks is different than wheeling in Moab or wheeling on dirt and mud, so building phylosophies are also different. If you want to run moderate trails but look cool with tons of flex and big tires, it also doesn't matter much. Stoney, you want to wheel in the CA mountains and deserts, don't hang your springs beneath your frame. Unless, of course, you don't mind a good ribbing now and then. :D
 
i really appricate ur input goatman and i don't doubt u AT ALL! and i diffently respect u and know u have a lot of experiance!

i was just trying to figure out the logic about what u were saying! I am still deciding on this idea and looking at all the pros and cons to it! so thank you very much for ur (suggestions?)!!

stoney!
 
Seems like a lot of work and a lot of stuff in the way, just put in a coil link system or install a wider axle (D60) if all you looking for is more flex.
 
You haven't had fun until you've wheeled with the "kids" for a weekend!

Heckling their rigs is just the beginning!

CRASH

p.s. I'm just giving youi hard time Stoney........
 
Well, I don't think anyone doubts that I do serious rockcrawling regularly.

Everyone knows you are just as big a web wheeler as Jes, Paul Sinclair and :farmer: boy, so we should all take any advice you dispense with a big grain of salt. :D

CRASH
 
This would be the # 1 worst mod you could do to an XJ. There are a few simlpe things that make the XJ work so well in the rocks, the recessed spring hangers rank right at the top of that list. Take a look at the amount of work the Toyota guys put into frenching their spring hangers, or consider that TJ's sacrifice rear control arm angles in order to mount them flush against (or in) the frame.
Paul
 
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