If you can measure and weld you can do this. The lower arm is easy you just need the drill template to drill the new holes in the brackets, a little trimming and bolt the arms back up. Once you have done that you adjust everything up to get your baseline measurements before you cut the upper axle brackets off. From there you set the new brackets, tack them in place and cycle, cycle, cycle to make sure everything is in its happy place before burning it in.
Dave Kishpaugh's (Jeep West) geometry correction brackets are now available
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Thanks @Blackjack. Seems easy enough. @Wildman was generous and let my borrow his template to redrill LCAM, and that is done. Dave recommend that I not redrill LCAM at axle. So question is, how do I know correct height to go on UCAM?
Were you thinking of going mid arm? I know that Dave does not raise the lower for most of his current mid arms. So if you are staying short arm you will want to move the axle side of the lower up when you do the uppers. You cannot move the lower at the axle until you are doing the uppers as the loss of link separation will cause issues.
@Blackjack yes, I am going to stay with my short for now as everything is almost new. In the pictures it appears the LCAM at axle is just a bit down from the center line of axle. I cannot tell how tall the UCAM brackets are.
Ok so if you are thinking mid arm later you will not want to trim the lower control arm brackets like I did. I do not know what height Dave is going with exactly but my Nth Degree brackets allow for 2.5 and 3.5 inches up from stock. Dave has mentioned his are less than 3.5 because you either have to run a body lift or over three inches of bumpstop extension so the brackets do not hit the tub.
Thank you @Blackjack I will shoot between 2.5 and 3" over stock. I have a 1.25 body and UCF zero clearance, hence the very high pinion angle.
short arms absolutely need to have the lower control arm mounts redrilled when relocating the upper control arm mounts higher. if you don't want to re drill, the frame end mount has to be relocated another 2.5" lower than stock, tha'ts a rock grabber. just moving it down 1" at the frame end doesn't give up clearance because the stock brackets hang down there already.
if you run a 24-26" mid arm with re drilled axle end mounts or center mounted, the control arm bolt will barely hang below the frame enough to get a bolt to pass under it. this is really fussy because the axle end doesn't have much separation. if you use the axle end and go up more than 2.5" over stock, you just created a clearance issue that hinders uptravel and needs bent arms, tunneled body or bigger body lift. the best example I can give is fabtech, rough country and rusty's share the same bolt for the frame ends due to where the antisquat ends up from the lack of axle end separation, BDS does the same thing in the form of a shorter upper arm and frame end bolt the is below the bottom of the frame. Rockmen Rockstar is an example of the other way, having stock separation at the axle end and lower frame brackets that hang 2.25 bolt center below the frame. we can't get enough antisquat even with the frame end in the lowest hole to create any better drivability than the stock short arms with a lift. the geometry correction brackets put the rockstar uppers in a position that you can adjust it to do what you want and have the dead solid feeling.
they are 2.5", the track bar is 3.5". using 3.5" upper position with the nth degree redrill templates makes the suspension bind up hard under articulation well before it hits even 3" of bumpstop extension in a 12" travel range with a 17" rear spring free length.
@David Kishpaugh thanks again for the insight. We have talked several times about my rig, and really would like to bring it to you, but it is just not feasible right now. I know I will no get close to what your mid arm can do with my short arms, but I need to put something together that will work for 2-3 years. I have redriled the frame LCAM with the template, but did nothing with the axle LCAM as there is not much room to redrill with the Artec axle setup. Also my LCA are turned all the way in, and my pumpkin is about 1/8" away from my gas tank even though I have raised it 1.25" with my body lift.
Brianj5600
TJ Expert
@David Kishpaugh is the binding with the upper in the top hole due to the 4 control arms or the difference in height of the axle and frame mount for the track bar? Would lowering the frame side track bar mount reduce bind? Or cause another problem?
Sign me up for Geometry Correction. I just ordered a set from Dave.
There is some Maths that I cannot compute.
. Does it involve Pathagoreans Theron? 
?Maybe it's do not mess with something you know nothing about?
I hope you document the install in your build thread! I am very intrigued by this but my list is so long! I have all the parts for my spring upgrades except the control arms which I am saving up for now.
Pressurized
TJ Enthusiast
Just ordered the brackets from Dave. I will be working with Jason from Absolute Offroad on the install. My guess is around 3-4 weeks, I'll detail in my Jeep thread.
Pressurized
TJ Enthusiast
I just saw this post... And while I'm new to TJ's, I am somewhat of a geometry guy. Your arms are near parallel now which puts your instant center in a very unusual spot way out in front of your Jeep. It's traditional to say that you want your instant center close to intersecting the anti-squat line per the attached diagram. Instant center above the line causes the body to rise under acceleration and instant center below the line causes squat under acceleration. For traction, I believe we are looking for instant center at or below the anti-squat line. But the main thing that caught my attention was that with your parallel'ish arms, you are not getting any axle roll during compression which would arc your springs in to alignment and would also rotate your pumpkin away from your gas tank during compression.
Your upper axle mounts need to be raised to get a proper instant center and it will correct a number of other things you have going on. Just my .02, hope it helps.
Not a perfect diagram for our Jeeps, but it gets the point across. Guys that have done a lot more experimenting with Jeeps can hopefully add where our instant center works best. It looks to me that with the flattening of the lowers and the raising of the rears upper at the axle, we are looking to reduce our anti squat and get the instant center down below the anti-squat line.
@Pressurized , thank you for noticing and your suggestions. Check out what I have recently done to my rig, and used a calculator -
https://wranglertjforum.com/threads...4—nv3550-conversion.34980/page-11#post-764929
Here is another thread with it finished, I have to put the calculations in the calculator, but this is the end result -
https://wranglertjforum.com/threads...-it-binds-suspension.45203/page-3#post-786587
I am going to experiment putting the LCA in the OEM position on the frame, instead of the suggested by Dave and Nth Degree, and this would get as you suggested, my instant center close to the anti-squat line. The calculator shows it currently at 72%, and if I move the LCA, I will be almost right on the line.
Pressurized
TJ Enthusiast
Thanks for the links... Your rear track bar thread is very applicable.
The upper axle mounts do get replaced with this kit and the are raised approximately 2.5” if I am not mistaken (same overall amount as the lowers). Your logic regarding instant center is sound. Short arm lifted Jeep’s end up with insane amounts of anti squat. This kit brings the rear geometry back closer or equal to factory geometry depending on how much lift you have.
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