Thinking of designing my own lift, and want input from ya'll

swyszomirski · **Joined:** Sat Oct 01, 2005 2:59 am **Posts:** 286

Well, I am in college studying to become a mechanical engineer, and recently, some of my physics classes have taken me into the math of frames and trusses, etc. And it got me thinking, what about designing new A-arms for my KJ, long arms that allowed more lift without the CV joint problems cause with the A-arm longer, the angle on the CV would be less. I have been looking at Chaos Baja suspension designs, and the like, and I think I is quite possible to design and have made. But I wanted input from the masses here as I have never designed a suspension component before.

Please, talk with me.

Stephen

TheJawsOfDeath · **Joined:** Sun Nov 05, 2006 3:56 am **Posts:** 305

Longer control arms that move the wheel out farther, widening the track. this along with longer axleshafts will decrease the angle on the CV joints that causes them to fail. Also stronger CVs with the longer axles.

Jeger · **Posted:** Fri Feb 16, 2007 7:01 am

Cant help you much with specifics, but longer control arms would be key to a good lift. I was also pondering the possibility of moving the diff closer to the center to allow for longer axle shafts yet. But something like that would probably end up being a huge lift 6" or so?? And would probably require a custom cradle just to get started. But if it could be done it would be the ultimate IFS lift for the KJ.

dgeist · **Posted:** Fri Feb 16, 2007 10:03 am

swyszomirski wrote:

Well, I am in college studying to become a mechanical engineer, and recently, some of my physics classes have taken me into the math of frames and trusses, etc. And it got me thinking, what about designing new A-arms for my KJ, long arms that allowed more lift without the CV joint problems cause with the A-arm longer, the angle on the CV would be less. I have been looking at Chaos Baja suspension designs, and the like, and I think I is quite possible to design and have made. But I wanted input from the masses here as I have never designed a suspension component before.

Please, talk with me.

Stephen

How about some pragmatic requests:
- Make all the wear parts serviceable (like with replaceble balls and what not).
- Incorporate some reinforcements in the design for common impact points from rocks/etc and avoid sharp angles, etc on the outer edges that snag on things.
- if you do the upper arm making it adjustable (to match the geometry of different base ride heights) would be nifty.
- Make it bolt-on

Jeepjeepster · **Posted:** Fri Feb 16, 2007 11:12 am

Thats an awesome idea is you have access to the machines and tools needed to do that.

-As its been said, long A-arms mean longer cv-joints. Not to sure how you could find longer cv-joints.

-If you lifted it higher than 3", you would really need new spindles to take the angle off the tie-rod and move it up. You may also need to lengthen it unless you could work something out with the a new spindle.

-Brake lines and ABS lines(If you have abs) would need to be longer.

CJ10chris · **Posted:** Fri Feb 16, 2007 12:42 pm

We need some custom knuckles!! I have a set of WK knuck's that I think would work but aside from making a set of lower A's or modifing the mounts on the KJ cradle to use WK arms. My fear of making my own lowers is getting the angles right so you could still get it back to factory specs. I guess you could center the diff more, it would help and switch the yokes ( t-case and diff) over to a traditional u-joint like in other Jeep setups. So start building some stuff for us to see!! I know there is alot of gripes about companys not building stuff for the KJ's, but if we keep on fabing up our own stuff and wheeling it, it might spark some intrest in the aftermarket to start making some products for them. Time will tell, but in reality it still a pretty new model and it will never have the support like the Wranglers do. So its up to us!

renegadekj · **Posted:** Fri Feb 16, 2007 1:59 pm

while your at it, please design a new IFS front differential!! i dont think i would want my kj lifted more than 2.5' anyway as far as iam concerened the weekest link of my kj is the front differential! My 2 cents anyway!

KJNick · **Joined:** Mon Jul 11, 2005 12:00 pm **Posts:** 56

If you go changing suspension geometry, you might want to do some research on suspension design. By modifying lengths and angles, you can change the roll center, create excessive bump steer, and change the anti-dive/anti-squat properties of the front end. All these affect how the front end will handle. Minor changes probably won't have excessive effect on the geometry, but major changes can really make a good handling suspension go bad quickly. Not saying it can't be done, but as an engineer, I'm sure you can appreciate the value of doing it right.

swyszomirski · **Joined:** Sat Oct 01, 2005 2:59 am **Posts:** 286

I have been looking at a lot lately. Mostly, baja suspension and the like cause it seems to fit what is needed. As for the bolt in type lift, yes it would be, or at least I am going for that. I am looking for a suspension book that I read about at an engineering forum, so I am trying to do all my hw. Actually, during my marketing class today in college I was designing how I wanted to supension to work

, I sat in the back so the prof. didn't see... I was thinking of using MOOG ball joints and some of Al's stronger CV's. A steel center diff would be nice, I have heard that I think it was yoter that had them. There is so much to look at! I will keep you posted, but first I think I am going to design it in Inventor because one thing I don't like about most of the lifts out there now is the upper ball contact at full droop. Ok, that's enough for now, keep any ideas coming.

Laters

Stephen

Thinking of designing my own lift, and want input from ya'll

Who is online