SPC UCA Alignment Sheets

My buddy is installing my SPC UCA's this weekend, and I have an alignment appointment on Monday. I told him to set them at "E" to start out. If they need to be set to a different setting, how difficult is this to do after they have already been installed on the truck? What is the easiest procedure to change the setting, while on the truck? Is this something that the alignment shop can do easily?

You can do it in the parking lot with a torque wrench, a 1-1/4" socket, and a jack in about 5 minutes per side.
 
My buddy is installing my SPC UCA's this weekend, and I have an alignment appointment on Monday. I told him to set them at "E" to start out. If they need to be set to a different setting, how difficult is this to do after they have already been installed on the truck? What is the easiest procedure to change the setting, while on the truck? Is this something that the alignment shop can do easily?


Did you research the alignment shop your bringing it to? I'd make damn sure they have aligned lifted vehicles with SPC arms before. I would also print out the SPC instructions and give them to the alignment tech. Any good tech will adjust them with ease.

I'm on F and have everything within spec. But my alignment guy is very good and has a lifted rig himself. Find a good shop and let them do there job.
 
The last couple of evenings I've been playing with suspension..

I don't have proper alignment gear (I wish I did!, no one here understands lifted trucks) so I just have a cheapy laser setup that only measures total toe..


Anyway I was fed up with how my truck drove, I had SPCs installed, in "D" position, and as I have fairly disked wheels was getting the usual rubbing at the rear of the front tub... my "temporary fix" was to crank up the height, as I was going to "find a decent shop and get it done properly".


Anyway long story short, the last few evenings I have removed my coil overs, stripped them down, painted the springs, freed the adjustment plates etc, and re done all the alignment.


Using the alignment guide TSRM, I figured that as I was running "+25°" from factory with the SPC compensation, (Position F) and a bit of trial and error (running the truck lower than I plan to, to allow for compression, and turning the wheels lock to lock until they cleared). I ended up with rear cam +8, Front Cam -7. Later compensated for the passenger side being rear +9 as that side always seems nearer on my truck. I didn't want to max out as I wanted to give the alignment shop some wiggle room.


For the sake of it I worked out the "average" distance on the tie rod ends and centered them, then moved forwards and backwards a bit to settle, and the toe in was .5°.. Not bad just for "going by numbers" (we'll um, ignore camber for now. It was set to rough centre of the SPC adjustment, so will be correctable from there, currently looks positive). Best of all no rubbing (yup only 33s, but back spaced). I lifted the coil overs a little more and now even with "exuberant" braking and cornering, no rubbing, it also rides a billion times better now there is more droop, and the springs aren't insanely preloaded (no suprise there). Toe looks to be out of spec again, (+1.5°) but I can dial that out, I'm pretty pleased it drives as well as it does for a "DIY" alignment. I can get it better... and hopefully it'll be near another for some idiot alignment tech to "polish" it, and not revert it back to scrubbing.... I need to find a perfectly flat place so I can get a more accurate measure on it.
 
You can do it in the parking lot with a torque wrench, a 1-1/4" socket, and a jack in about 5 minutes per side.

Thanks. Good to know it is that easy.

Did you research the alignment shop your bringing it to? I'd make damn sure they have aligned lifted vehicles with SPC arms before. I would also print out the SPC instructions and give them to the alignment tech. Any good tech will adjust them with ease.

I'm on F and have everything within spec. But my alignment guy is very good and has a lifted rig himself. Find a good shop and let them do there job.

Good advice. I did visit the shop prior, and showed them the UCA's. They didn't seem to have an issue with them. They do align lifted trucks, and have aligned my lifted 4Runner a few times before also. The main difference this time will be the SPC UCA's.
 
Good advice. I did visit the shop prior, and showed them the UCA's. They didn't seem to have an issue with them. They do align lifted trucks, and have aligned my lifted 4Runner a few times before also. The main difference this time will be the SPC UCA's.

Sounds like you'll be fine. But yes, take the instructions in with you and give them a copy. If nothing else, for the torque specs..
 
For some reason I am having a hard time grasping IFS alignment and why the G setting gets more clearance. Seems like more positive caster gets more clearance so why wouldn't A be better?

Really disappointed as I switched from D to G and lost clearance. Can someone look at these and tell me what happened?

SPC arms at D setting
608f2056aeff4c4170cb61983c7eb1b5.jpg


SPC arms at G setting (sorry it is sideways)
846e757079b88aedaf493d894f4fac23.jpg


And when people talk about "All the way in and all the way out" I assume they are talking about shorter and longer based on this. I may play with it at home since I have to pull out my brand new CV that isn't sealing at the diff.


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And when people talk about "All the way in and all the way out" I assume they are talking about shorter and longer based on this. I may play with it at home since I have to pull out my brand new CV that isn't sealing at the diff.


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All the way out...the upper ball joint.
It would be a camber setting...That 1 1/4" nut on top of the ball joint.
Slides in (towards motor) and out (away from motor).
 
Can anyone tell me which setting on the SPC UCA's would put the tire in the same position as the stock UCA's?

I'll be installing mine soon, and need to determine where to set them. I currently clear my 35's with my OEM UCA's, due to lots of hammering of the pinchweld/firewall area. I'd like to get more caster, but I don't want to move the tire any further back than it is now.

I was thinking of setting it at "F" to start. Thoughts?

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I just installed mine and did my alignment myself. I took Big Fish's advice and maxed the LCA cams in and out with the UBJ in position D. I have TE 17's with 1.5" spacers.

It did not rub anymore front or rear when I was done. But I had too much caster and a bit too much camber so it did not drive very well at highway speeds. Very twitchy and almost scary at times. So I re-did it and came up with this.

Front cams neutral
Rear cams pushing the LCA outward maxed.
UBJ as far outward as it would go using a thick impact socket.
SPC position "D"

Once it was fine tuned this got me into green all the way for factory alignment specs. I have done zero clearancing on the pinch weld and I get a very slight rub on the plastic. It drives like a new truck now though. Just a bit of pinch weld work and I will be good to go.

.4 Camber on both
3.1 Left Caster 3.3 Right Caster

Like others have said, your wheels and offset make a big difference. I would think with the clearance work you have already done, my final settings should get you really close even with the 35's. Good luck.
 
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For some reason I am having a hard time grasping IFS alignment and why the G setting gets more clearance. Seems like more positive caster gets more clearance so why wouldn't A be better?

Really disappointed as I switched from D to G and lost clearance. Can someone look at these and tell me what happened?

SPC arms at D setting
608f2056aeff4c4170cb61983c7eb1b5.jpg


SPC arms at G setting (sorry it is sideways)
846e757079b88aedaf493d894f4fac23.jpg


And when people talk about "All the way in and all the way out" I assume they are talking about shorter and longer based on this. I may play with it at home since I have to pull out my brand new CV that isn't sealing at the diff.


Sent from my SM-G930R4 using Tapatalk

Assuming your talking about firewall clearance. so, you lose clearance because your are "leaning" the UBJ backwards. Makes the caster angle greater but reduces clearance to the firewall. Increases clearance to the front though.

Shortening or lengthening the lower eccentrics changes caster and camber because the arms push (or Pull) either the front or the back of the spindle in or out creating a multitude of caster/camber angles

Try to picture this: Looking at your posted picture of the LCA cams. Look at the drivers side. Imagine putting your socket wrench on the rear cam and turning it counter- clockwise. Where the "+" and "-" symbols are heavy tabs protruding from the LCA that keep the camplates in place (the pieces the bolts go through that have the graduation marks on them and offset the LCA bolt which is the key to the cam adjustment) As the bolt/ cam asy turns, it is in an ellipse (because it is offset in the camplates) and moves the LCA bolt in (towards the motor-shorter)) when turning it clockwise and out (towards the wheel- longer) when turning it counter clockwise.

You only have to turn it 180 degrees using the graduation marks and the pointer above the cam plate. I've gotten my alignment done and watched the tech go round and round moving it in and out, in and out, and locking it in upsidedown. Not a big deal but it shows me the tech doesn't know how the cams work.
 
How exactly is caster measured on our 4Runners? What points on the vehicle do they use to create the angle measurement?

When the lower ball joint is more in front of the upper ball joint (when looking at it from the side) then you have positive caster.

Zero caster is like a shopping cart wheel. Straight up and down. Can draw a line straight through where it pivots at the top and where the "hub" is.
Ever see a shopping cart wheel as it's being pushed? Every little imperfection in the surface makes the wheel jut side to side. the only thing keep the wheel from not turning is the forward momentum of the cart.

Max caster is like a chopper motorcycle. The hub is way in front of the steering tube. The steering not easily affected by the road surface, and the wheel basically "wants" to go straight. Down fall is that the steering can be a little hard and sluggish.
 
All the way out...the upper ball joint.

It would be a camber setting...That 1 1/4" nut on top of the ball joint.

Slides in (towards motor) and out (away from motor).

Actually, when people say "all the way in and all the way out", they're referring to the LCA cams. Fronts go full in, and rears go full out.
That said, you will have positive camber after doing that, and you will need to use the SPC camber adjustment to pull camber in at the UBJ.
 
Actually, when people say "all the way in and all the way out", they're referring to the LCA cams. Fronts go full in, and rears go full out.
That said, you will have positive camber after doing that, and you will need to use the SPC camber adjustment to pull camber in at the UBJ.

Copy that, I thought we were talking about the SPC arm.
 
--------

I just installed mine and did my alignment myself. I took Big Fish's advice and maxed the LCA cams in and out with the UBJ in position D. I have TE 17's with 1.5" spacers.

It did not rub anymore front or rear when I was done. But I had too much caster and a bit too much camber so it did not drive very well at highway speeds. Very twitchy and almost scary at times. So I re-did it and came up with this.

Front cams neutral
Rear cams pushing the LCA outward maxed.
UBJ as far outward as it would go using a thick impact socket.
SPC position "D"


Once it was fine tuned this got me into green all the way for factory alignment specs. I have done zero clearancing on the pinch weld and I get a very slight rub on the plastic. It drives like a new truck now though. Just a bit of pinch weld work and I will be good to go.

.4 Camber on both
3.1 Left Caster 3.3 Right Caster

Like others have said, your wheels and offset make a big difference. I would think with the clearance work you have already done, my final settings should get you really close even with the 35's. Good luck.

This is exactly what I had to do. Front cams in the middle. Rear cams pushed out. UBJ brought almost all the way out and caster set on "D" My thinking was that with my 3" lift I lost 2 degrees of caster and my camber range was shortened. The SPC arms come with 2 degrees built into them on the "D" setting. All I had to do was install the SPC arms and re range the camber. My readings are almost identical to Cowards.
 
Playing along with rKntoy...am just stalking him cause I like his T4R and he lives in the same town... :)

Seems like G would move the UCA to the front.
I guess with the interaction of the Cam bolts/LCA it pushes the tire to the rear?
Thinking the 'G' setting is like the stock setting.
 

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Playing along with rKntoy...am just stalking him cause I like his T4R and he lives in the same town... :)

Seems like G would move the UCA to the front.
I guess with the interaction of the Cam bolts/LCA it pushes the tire to the rear?
Thinking the 'G' setting is like the stock setting.

Have I met you yet?

I think the part that is throwing me is the ability to move the uppers in relation to the lowers. People say the most firewall clearance is with G so I am going to make another stab at that. Alignment shop has the front cams 180 degrees from where they should be so I am going to adjust tonight.
 
Have I met you yet?

I think the part that is throwing me is the ability to move the uppers in relation to the lowers. People say the most firewall clearance is with G so I am going to make another stab at that. Alignment shop has the front cams 180 degrees from where they should be so I am going to adjust tonight.

Don't think we have met.
I might have seen your T4R at a Discount Tires, was so busy I just walked in and out and went to LesSchwab's...a couple years ago, you didn't have 37's on it...if that was you.
BlackWorkInc and I got into half of that that Edison Butte trail...neither knew what we were getting into.
Did a quick drive and shoot with Shearn and Blackworks and a friend. Only T4R.org crew I have played with.
 
As I prepare to install SPCs in the somewhat near future I have to ask, how do you set "UBJ as far outward as it would go using a thick impact socket"?
 
As I prepare to install SPCs in the somewhat near future I have to ask, how do you set "UBJ as far outward as it would go using a thick impact socket"?

The UBJ slides in an oblong slot in the UCA to adjust camber and is "locked" in by that big nut (28mm?) To make the camber more positive, move the UBJ outward. With my settings I described above, my UBJ was almost as far outward as it could go.
 
The UBJ slides in an oblong slot in the UCA to adjust camber and is "locked" in by that big nut (28mm?) To make the camber more positive, move the UBJ outward. With my settings I described above, my UBJ was almost as far outward as it could go.
I saw that, didn't realize it was an additional point of adjustment, but it makes total sense.

I guess my question is:
What settings should I start with when I install my SPCs with Sequoia 17" rims and 32" tires with 1.25" spacers?

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