CA and caster q's

[Bones]

Anyone know what the length of RE's fixed length control arms are for their drop bracket kit?

Also, what is the relationship between arm length and caster?
(What I mean is for every ___" of LCA extension or UCA shortening, you move the caster angle by ____*).

I put in new to me 6.5" springs and have a contact issue between one of my springs and the sway bar. I figure it has to do with running a negative 5* caster or so (Yes I mean tipped the "wrong way" but just a guess, will measure it tomorrow, but my pinion angle is great :D ). Need to find a good middle ground between caster and pinion angle for 6.5* of lift.

Bones :skull1:

[RCP Phx]

They only have one set for all the set-ups.The lower's are 16" and my upper was set at 15.5".

[MaXJohnson]

What's wrong with negative Castor? Just drive around in revearse ;)

Here's a chart that should get you in the ball park (YMMV)

Lift = Change (delta)
1" = -0.78°
2" = -1.56° (-0.78)
3" = -2.32° (-0.76)
4" = -3.10° (-0.78)
5" = -3.89° (-0.79)
6" = -4.70° (-0.81)
7" = -5.57° (-0.87)
8" = -6.50° (-0.93)

As you can see, it's roughly 3/4 per inch of lift, increasing slightly the higher you go. Don't forget to factor in the 4" brackets if you're using them.

[Bones]

Ok, I think I figured out the stuff I was looking for. Instead of trial and error under the Jeep trying different control arm lengths to set my caster (it was -3* BTW) I decided to use my brain.

After bottle or two of aspirin to control the pain :wow: I was able to do a mock up of the front control arm and axle set up in cross section. I then adjusted the "arms" length and was able to measure the change in caster.

It appears that caster is changed roughly 4-4.5* for every .5" of control arm change (4 for the lower and 4.5 for the upper). For some reason it appears there is a mild penalty built in if moving both arms at the same time (even opposite of one another).

I plan to extend my lower arms .5" and my upper ones .25" and figure on a caster change from -3* to a positive 3.25* give or take. If I pick up front vibes again I'll just start unhooking the driveshaft on long runs.

Bones :skull1: