1/4 elliptical (1 Viewer)

[boostedz31]

I have been doin alot of research on the quarter ellip. suspension. I am curious if anyone has any personal experience with them? I've read alot about medusa, and have only found 1 other cruiser with a 1/4 ellip. suspension. I have even gone as far as searching for jeeps with 1/4 ellip.. I have also done hours and hours of reading up on the 4 link suspension.. roll axis,link placement and length, center of gravity... ect ect..

Does anyone have any personal experience, useful knowledge or tips about this subject?

I found a kit for a jeep called the rubicon express yjla ( yj long arm ) that appears to use 1/4 elliptical front and rear.. can it be used on the front?

Can a 1/4 ellipted rear see a little street driving? I live a couple miles from the local trails.. and sometimes trailer to my home town, unload and drive around ol back roads to some good fishing holes/ trail heads..

I have fab skills and the tools/shop to do it. I have been thinking about spring over for some time, and wanted to go s0a this spring. I have been searching for springs with the center pin offset enough so that my approach angles are vertical.. I want lots of wheelbase and to be able to adjust my suspension... So basically that makes me feel like the leafs need to go. Then I can get rid of spring hangers sticking out, and that big gay front bumper.. Only problem is I can't justify spending the money on coilovers. I do have easy access to f350 springs, AND I do like to be different.. 1/4 elliptical just seems to be the way to go.. (on the rear, I am under the impression you cant go 1/4 ellip on the front.. So ill turn my research over to coil springs for the front once this chapter is finished...

Thanks for anything that is useful on this subject.

here are some pics of what we are working with, and my little hood ornament~

 

[zornff]

My rig has 1/4 elip springs and they work awesome. The spring packs are easy to build, i used fj60 rears. 4 link opinions vary, i went the easier route and bought my 4 link kit from Proffitts. The set up i was running prior to my current build wheeled great, and i also drove it all over town. It did have some body roll, but was manageable.
On my current build i beefed up the spring packs to handle more weight. If i need to i will add air bags to raise it up when loaded.

Good luck with your build, Mike

 

[boostedz31]

awesome man. Glad to hear some good news. Do you have a recommondation for rod ends?

 

[zornff]

I've had good luck with heims, others use Johnny joints. I moved the rear axle back 12" with the 1/4's, to 105" wb, The front is soa moved 4" forward with flipped stock 40 front springs, with out boarded fj60 axles. If you are looking for control arms, i have the ones i took off for my new build that are 36" from Proffitts if you go that direction.

Mike

 

[Sputnik40]

Woody posted a few good pics of his quarter ellip in his unfinished build thread - here: FJ40 rear 4-link - Land Cruiser Tech from IH8MUD.com

 

[woody]

Big fan of mine.....very streetable as well.

Good:
cost
adjustability
balance w/ front

Bad:
added fab time
weight

Mine was done 'on the cheap' and has worked well for years...IMO, hard-mount the frame side and use thick leaves to build the packs....GM/Ford rear springs work well, 2-1/2" or 3" wide, but thick. I used cheap 5/8 bore 3/4 thread QA-1 heims and have yet to replace one.

Other than raising the axle-side upper mount to change antisquat-rollaxis values and splaying the lowers a bit wider on the axle, i've made few adjustments to mine.

 

[bikersmurf]

Peterson's 4x4 Mag had one 10+ years back a jeep on front cover w/ 1/4 elliptical rear and a buggy leaf up front. Heep had 5' of articulation as tested by fork lift. If I recall it had a four or five link setup in rear as well as a pivot where spring shackle was in the above linked pictures. The pivot was perpendicular to axle axis so as to allow more axle drop without torquing the leaf springs as much.

Someone may even be able to dig up a copy of the Mag.

 

[LT]

I used F250 leaf springs like Medusa and they work great. Lots of stability off road and tons of flex at hand.

I would build your own custom 4 link for your FJ40. No one kit is going to perform the best on your rig. It all depends on your drivetrain, the over all height desired, and wheel base.

 

[woody]

Woody posted a few good pics of his quarter ellip in his unfinished build thread - here: FJ40 rear 4-link - Land Cruiser Tech from IH8MUD.com

in looking at those pics, some changes I'd make now:

1> wouldn't bother trying to design a 3-position mount for the frame side upper....never did use that....

2> gusset/box the frame side lower mount...mine are trashed...

3> splay the lowers a bit more on the axle tube to minimize rear steer (current rendition on mine has that)

4> raise the upper mount on the axle another inch or so (mine is that way now)

 

[boostedz31]

thanks a ton for the info guys~ Ive very please with what I have learned so far.

Anyone have any knoledge about a front 1/4 ellipt.?

 

[Tapage]

just wondering .. if you got the chance ( cheap or a good deal on right coils with right rate ) why not coils and 4 link rear .. instead of 1/4 elipitc . ?

 

[boostedz31]

I want to do 1/4 ellipt in the rear for a couple reason. I like to be as different as i can.. That's why I have a fj40, not a jeep...a datsun with a v8 instead of a camaro/mustang.. etc..

the more realistic reasons are cost.. and It will be alot easier for me to adjust lift/spring rate with different leaf combinations. I have alot of leaf packs to cut up.. and I don't have any coil springs..

thanks for all the input on this subject guys.. feel free to keep it coming

 

[DHONDAGOD]

I did mine for the very same reasons your stating. I studied Jacks (Medusa) FJ45 for along time before committing to cutting up my rig.


I have alot of body roll due to a low roll center on mine but it drives and wheels very well. IMO my links are too long and if I were to do it again Id make them a bit shorter.


FWIW it was alot easier to chop the back of the frame off and link it them build a frame to fit the suspension and support the body than try to fit everything around the stock frame. Trust me on this.

Im also (for the same reasons you posted) am eventually link/q-lipt the front as well...

Link to my build thread on Pirate: Dhondagods Fj40 Build - Pirate4x4.Com Bulletin Board

Chris

 

[boostedz31]

awesome.. front 1/4 ellipt? Ive been watching your build. Can you give me some info on your plans for the front ellipt?

 

[rsc71]

i have one that came in a kit form...the springs are held in a box basicly and mounted in the hangers and pivot.there is also adjustable bump stops to adjust ride heigth.

 

[hudyhue]

man chris your going to do the fronts too....have you broke a pinion after the up grade?

 

[utahbeemer/lc76]

Looked at this Idea of 1/4 linked suspension. The only thing that bothers me is how to attach the springs to the axle tube. All the way's I've seem look fragile, maybe I'm overly cautious or I don't see some thing any one wish to comment ?