Initial setup of adjustable UCA?

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70Duster440

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Maybe 72bluNblu will chime in here since he's been around the block a few times. Here's the project and a little background...
  • Ditching the the Fatman 2" drop spindles and .89 torsion bars (all of which I was mostly satisfied with) and putting the stock spindles back on with 1.03" bars from PST.
  • Replacing stock bump stops with Energy Suspension shorties.
  • Keeping RMS adjustable UCA's (circa 2007) that have adjustable bushed ends.
  • Changing from 24.8" tire to 26"
  • Goal is 0* to -.5* camber and 3* caster (for manual steering).
I believe the Fatman spindles are a little taller than stock a-body so when I swapped spindles and put it back together for a looksee it had uber negative camber and (of course) mile high stance.

With the tire off and jacking the suspension up to approximately simulate the same ride height I put a angle finder on the face of the rotor. With both cams maxed all the way out I could almost hit 0* camber. Time to adjust the UCA's.

Now, RMS instructs you to start with the ends two turns out and this "will leave plenty of adjustability on 99% of all vehicles". That's where I had set them before and supposedly the alignment guy had been able to get what I wanted for specs years ago - but who knows for sure. I backed the ends out another 3 turns each and with both the cams more or less in the middle of their adjustment range I can now hit 0* of camber with a little leeway.

For caster, the RMS arms use washers as spacers/shims on either end of the bushing. So, essentially, I have 3 ways to adjust caster: move spacers to the front of the pack, screw ends in and out in opposite directions, use the cams, or any combination.

I transferred some lines to the floor best I could using a laser level and square - including lines 20* left and right of center. Using the laser level and angle finder on the rotor I found that a little more than 3/4 turn of the wheel in each direction lined up with the 20* marks - but no real change in caster with the cams in more or less neutral position and zero camber. (Higher turning angles registered some caster).

I'd like to be get it set up to the point where a shop can dial in my spec goals as easily as possible using the cams - and not have to pull the uppers to move washers around or adjust ends. So, all this to say I'm looking for suggestions on initial setup of these control arms.

UCA2.jpg
 
Crickets, eh? No problem. Current RMS instructions for their arms say to start at 1/4" out on the ends (vs 2 turns) which is at least double. I ran them out equally almost 7/16" to get the cams near neutral and still allow a lot of adjustability. I may invest in a Longacre gauge to make final adjustments rather than rely on some alignment dude who will settle for 'ballpark'.
 
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