SPC UCA owners... GET IN HERE!!! (caster settings)

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So with a Slee diff drop and SPC's UCA there is a higher front end measurement?

As long as you're measuring what droop do you have at 22"?

Or by now at 22.5"?

So with a Slee diff drop and SPC's UCA there is a higher front end measurement?

Not sure I fully understand... Are you asking if there is potential to go to 22.5"? I didn't take any pre-SPC measurements so I can't recall exactly where I was before I switched them out. I do remember lowering the front end via torsion bar adjustment over the last couple of years though. I think when I first set the whole lift thing up a few years ago, I was running a 1" rake, so 23.5" rear and 22.5" front.

As long as you're measuring what droop do you have at 22"?

I'll get a droop measurement next time I get it on a floor jack (probably this weekend).

Or by now at 22.5"?

Again, not sure I fully understand... I was basically asking if I can comfortably to to 22.5" up front (given my build specs.


Anyone know the stock center hub to fender measurements? I want to know where I presently stand.
 
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Mine at front stock was right around 20.25". Not sure if anyone had ever messed with it. Now I'm at 21.5".

I'm no lift other than torsion bar crank.

@Bloomer picture for you of the new icon bracket I was talking about.

image.jpg
 
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SPC alignment specs below. I posted this in the Icon thread, so excuse the duplicate post but the SPC info may not be as easily found in that thread vs. this one.

Icon reservoir fronts went in the same day as the SPC arms. Used the recommended reservoir location and everything went in easily. I used location "D" on the arms as that allows for the most droop. You'll see what I mean with the location of the ball joint and how it mounts to the SPC arm. At stock height my alignment specs were 0 camber, 0 toe and 3.4 degrees caster. So at stock height expect the extra caster to firm up the steering...but the front ride and handling improvement were a huge improvement over stock.

Truck goes down the road beautiflly. I did add shocks and upper control arms all at the same time so hard to tell what the incremental differences are but overall I'm super stoked.
 
SPC UCAs install and alignment completed

- Front lift height - 21.75" wheel center to fender
- Diff drop (yes/no) - No, not yet
- Tire size - 315/75R16
- Wheel spacers (yes/no) - Yes 10mm front, none in the rear
- Caster star plate settings - D
- Any other useful data - no body lift

Below are the post install and alignment numbers. So far it seems better but I haven't driven it much yet. Road trip to NC Saturday with a trailer in tow will be a good test.

upload_2015-3-26_7-1-4.png
 
My pre lift height from center of hub to fender lip was 19" front (stock).
Great info here, still fine tuning mine, recovering from shoulder surgery. Can't wait to clean up the ride.
 
@coldwiz, at 21.75" you'll more than likely have some street/hwy torque steer...and although I can't recall droop at this height methinks you might be slim in that dept.
 
@spressomon good info. I thought 22" was about the max with extended travel front shocks and an aftermarket UCA. So you are 21.5" or??
 
@spressomon absolutely there is torque steer at times but I was hoping that getting the caster back in spec would help with this. Or would a diff drop decrease the amount of torque steer? It seems to be less aggressive after the SPC's but again behind the wheel time has been limited.
 
@coldwiz: The diff drop will help in the torque steer department and CV longevity dept (you definitely will want to add the diff drop sooner rather than later)...but even at ~stock height our CV angles already rest at an angle. You'll just have to test the front height and find what you can live with for what you do.

@Slickspawn: Subtracting my 1" body lift I am at an effective front suspension height of 19.5"- 20" most of the time; sometimes more for all things Utah ;); but then back down for everything else.

This is the real value of the 1" body lift...yeah I know I sound like the body lift prophet but given how sensitive our front drive system (CV angles) and steering ends are with even a little lift...the BL goes a long way for preserving steering feel, minimizing/eliminating torque steer and helping in the parts longevity dept., while providing increased tire to fender clearance.
 
Do the SPC UCA offer more clearance? Wheel spacer optional with 315's?
 
You will still need wheel spacers with 315's on the stock wheels.
 
What is the SPC part # for these arms?

I see that Slee sells them, it looks like several SPC arms are available on Amazon too(not sure about this specific application).
Are there any other retailers to consider purchasing these from?
 
What is the SPC part # for these arms?

I see that Slee sells them, it looks like several SPC arms are available on Amazon too(not sure about this specific application).
Are there any other retailers to consider purchasing these from?

Metaltech4x4.com
 
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Got an alignment yesterday with the SPC's in. Went with position "C" on the ball joints and had them dial in +4 degrees of caster. Initial report is a little more steering effort, off center. A little more stability at freeway speeds. A little less clearance between the firewall and tire. I'll report back in a few weeks.
 
@hoser I feel like I should know this but how is your truck set up? Tires, lift, etc.
 
2" AHC lift with 285 width 35's and 1" wheel adapters. Previously had wide 35's that would rub the inner firewall on suspension compression and full lock. Rubbing went away when I switched to 285/75R18. Decided to dial in additional caster... which also reduces the firewall clearance.
 
I am totally lost still.

I am aligned with an ~3" lift, Diff drop, 35" tires, and setting of "D". My only problem is, is that my tire will rub the UCA at decompression (coming off of a bump, higher speed turn, etc.)

I want to pull the tire away from the firewall just a hair.

What should I do?
 

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