Fox Aje k member geometry

Aragon13

New Member
Aug 24, 2023
3
0
1
United States
Hello everyone, just a quick question since I cannot find any info out there on this. Does an AJE k member use stock geometry? I have a lowered 87 hatch that already has the aje k member and control arms on it and we were looking to convert to 96 front spindles that we had extra.
Also does anyone know if their control arms can have Steeda X2 ball joints pressed in?
Thank you!
 
  • Sponsors (?)


It places the steering rack in the standard Fox location meaning 94-95 spindles are preferred. With 96+ spindles you’ll have to live with some bumpsteer issues as the tie rod and the tie rod mount on the spindle need to occupy the same space and since that’s impossible you will just have to deal with it.
 
  • Like
Reactions: 1 user
I have an AJE k member, lowered on coil overes, and 98 spindles. With no spacers in the bump steer kit it handles pretty good. No major bump steer. However, 5L5 is 100% correct. The tie rod end wants to be set up right where the spindle arm is.
 
Okay I think we can make this work, would you guys recommend investing in a bumpsteer kit to help the geometry, Or can I get by with a set of fox tie rod ends? If yes on a steer kit would I want a fox or an sn95s kit? Car has a fox rack
 
You cannot correct the bumpsteer geometry with any parts.

96+ mustangs drop the steering rack down about 1” so ford redesigned the spindle mount to account for that by lowering it down 1” as well.

with the 79-95 k-member the rack is 1” higher than the spindles were designed for so the tie rod ends would need to occupy the same real estate as the dropped spindle ends.

Since you can’t physically do that you are stuck with the result.

IMG_4626.jpeg
 
Drive my Coupe on 96+ spindles and the stock k-member for a couple years as a weekend cruiser and zero issues. When I swapped to the MM k-member I teamed the spindles and put the through bolt bump steer kit on it.
 
If you are lowered you could get away with stock fox outter tie rod ends. The bump steer kit I'm using is pointless with 98 spindles. I don't have any major bump steer at all but I'm using Monro struts, 12 inch 175 coil over springs, UPR coil over kit, and UPR camber / caster plates. For my driving style it's just about perfect. Very smooth ride with no bouncing and no noise. The rear is an 04 IRS with stock springs. This el cheapo suspension has worked for me for many years.
 
With my 96+ spindles on my stock k-member (I know this thread is about AJE K-member) I used offset rack bushings to move the rack down (most people move the rack up) and then modified my control arm mounts to raise them 0.5" up. I experience none of the above mentioned issues with the 96+ spindles.

I realize you may not be able to modify the control arm mounts, but you should be able to relocate the rack down with offset bushings. It should reduce any bump steer issues versus stock rack bushings.
 
What really messes things up is when folks add a bumpsteer kit to 96+ spindles thinking that is the solution for correcting the problem. This has nothing to do with the OP's setup and more of a generalization as to what i've seen on the forums and Bookface.

Bear with me for a minute and try to visualize this.

96+ cars lowered the steering rack. On the K-member, and the mount points on the spindles roughly 1" lower than 79-95 k-member/spindles. Let's ignore the Max Motorsports K-member which uses the 96+ lowered steering rack mounts (why they recommend 96+ spindles with their setup). Most guys are going to have a fox style K-member which uses the 1" higher mounting point for the rack.

So higher mounting point for the rack, and lower mounting point on the spindles. You may or may not get bumpsteer depending on how low the car is and other factors (offset rack bushings to drop the rack would help a ton here).

But assuming an impectect setup, the solution would be to raise the mounting points on the spindles or drop the rack. But, often times i see guys add a bumpsteer kit which includes spacers to push the tie rod ends further down, making the problem worse. This is the opposite of what you want to do as you want the tie rod ends higher. I browse over a ton of FB posts where folks say they run 96+ spindles on a stock K-member and added a bumpsteer kit to "fix the problem". 99.9% of people never even measure it because the entire process it a total PITA (i've done it...it sucks).

I'm not saying you can't make it work, but you just need to pick the right parts. If i were doing a stock K-member with 96+ spindles, i would get some offset steering rack bushings and install the rack in the lowest position possible, and then stick with stock tie rod ends to keep the mount point on the spindles as high as possible. You may not even ever notice any bumpsteer at all.
 
  • Like
  • Useful
Reactions: 1 users
What about a through bolt bump steer kit and putting the tie rod ends on top of the spindle attachment point?

I don't know if that can be done. I would think Max Motorsports would have thought of that if that was able to be done safely.

Flipping that around and mounting the tie rod on top? Would need to be mocked up to see what potential interference issues there would be.

:shrug:

1693317790837.png
 
Was just thinking that if a person put the 96+ spindles on a factory k-member Fox it might work on the top as it appears it would be correct by this picture:

1693333083597.png


I don't think it would work with factory tie rods but with the heim joints on the bump steer kits it might work but you would have to have the bolt through bumpsteer kit like this:

1693333858155.png
 
I'm not saying you can't make it work, but you just need to pick the right parts. If i were doing a stock K-member with 96+ spindles, i would get some offset steering rack bushings and install the rack in the lowest position possible, and then stick with stock tie rod ends to keep the mount point on the spindles as high as possible. You may not even ever notice any bumpsteer at all.
Basically what I did.

Mustang Front End Angles.jpg

When thinking bumpsteer you are shooting for two parallel lines. Pic shows the two lines you are looking for. One from pivot point of LCA to pivot center of the ball joint. The second from pivot point of the inner tie rod to pivot point of the outer tie rod. Theoretically perfect bumpsteer would have these lines perfectly parallel and the distances exactly the same between the pivot points (something I think is not possible on a fox without building a completely custom setup).

Moving my control arm mount points up (away from the ground) 0.5" and using offset rack bushings to lower rack (closer to the ground) about 0.5" gives me the 1" change that is needed to run 96+ spindles. I have stock fox rack, inner and outer tie rods and lower control arms (don't remember if I have stock ball joint or SN95).

If you can't relocate the control arms up, doing just the offset rack bushings will help versus stock rack bushings and 96+ spindles.
 
  • Like
Reactions: 1 user