OCHOHILL

Is anyone concerned about the lower ball joint? Before it was along for the ride and now the weight of the car is trying to pull it apart.

I would prefer the clevis at the LCA go away. That point has a big job and the cleavis doesn't look up to it.

eZ

Norm.. great info! I remember when I calcmy motion ratio it was real close to .9 like .87 or something.

Ocho -- That is a 5/8 chromoly clevis. Nothing is going to happen to it. Also the lower is boxed in with a screw-in ball joint that is that same as if it were placed on the upper. Only difference is that it is facing up instead of down?

OCHOHILL

The picture in post 72 doesn't look like a screw in ball joint. I found where someone else had a similar opinion.

Your build was mentioned on another site.

http://forums.vintage-mustang.com/mo...pension-3.html

OCHOHILL

Think of the ball joint this way, it's a ball in a socket. The lower joint in the original design was there for the ride. There were only some in, out, fore and aft forces acting upon it, not a lot of up and down force. Your configuration places the spindle and coil over in opposite force directions trying to remove the ball from the joint. What is keeping the ball in there? Try disassembling an old joint to see.

The old strut rod held the lower control arm taught and prevented twisting of the lower control arm. In truth, the old configuration didn't have a lot of twist going on. Your new set up will have a lot. If the lower shock mounting location wasn't exactly in betweet the center point of the ball joint and the center of the inner bushing, that alone will create twist. The inner bushing allows a certain amount due to the nature of rubber. If you unbolt the cleavis, can you twist the lower control arm? Even a little?

In your current configuration, what prevents the lower control arm from twisting? How much twist is there now? It it twists even a little, how many times will the cleavis take that before it breaks?

I made a solid mount lower strut rod the bolts to the strut brace like yours. I made this almost 2 years ago. The swedge tube threads to a rod that is welded to a 3/8" plate. This mimics the old strut rod although it is quite bigger. The reason I used such a large plate is because others had used 1/4" plate and noted stress on the plate.

Here is an early prototype:


I am a can do guy. I don't like it when someone indicates a problem without offering a solution. I would find a screw in ball joint that is installed in a similar application and graft it in place of the existing lower ball joint. While it's all apart, modify the lower shock mount adding a 'strut rod' like the one shown in the picture. The angle at which you mount it will have to be spot on. Any adjustment in the swedge tube will require loosening the bolts attaching the shock mount to the LCA. You won't have much if any caster adjustment through the strut rod.

If I am wrong, please tell me where.

tweet66

Ocho, I agree that there will be more stress on the lower ball joint and possibly more twist on the arm. To add to that, I belive eZ said he put a spherical bearing in place of the lower bushing, but he replaced the stock ball joint with a screw in unit designed for a lower arm. That should alieviate any concern with the ball joint popping out. The clevis is the only thing I see being an issue. I'm definitely doing this conversion on my 66 coupe, thanks to eZ's willingness to share his info (thanks again). I have already modified my stock strut rods to accept a heim and sleeve so I won't have the clevis issue (if there ends up being one) to deal with. I should eliminate any desire for the lower arm to twist. It'd be nice if there was a heim that only moved in one plane that could be mounted to limit twist but allow freedom of movement. Something similar to a clevis without the sharp edges that "could" lead to failure....

EDIT: Looking back at the pics i see he's running the stock lower ball joint....Another point we'll differ on, I guess. I've already modified my lower arms to use screw in ball joints & bearings and made the adjustable strut rods to use with my modified "stock" upper arm. My only changes will be the new arms and coilovers.

eZ

Allow me to go take a picture of how the existing LCA looks. The one pictured before hand was being used for mock-up

eZ

here is how the LCA looks now.


Uploaded with ImageShack.us

eZ

what if I replaced the clevis with something like this?



Uploaded with ImageShack.us

tweet66

The plate welded on the bottom definitely beefs up the arm. I think Ocho's concern was more with the ball joint itself pulling apart, not necessarily from the arm. If you can mount that style heim in double sheer that should work.

tweet66

Here's a write up by a friend who did the same mods on the lower arm.
http://budgetrestomod.weebly.com/roller-lcas.html
My setup is slightly different because I added 1/4" plate around the sleeve on the bottom side of the arm as well. I wasn't comfortable with just welding to the stock arm 1/8" thick material.