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Discussion Starter · #1 ·
In an effort to outdo edgy in mini-projects (like that's possible), I've taken it upon myself to do my own alignment.

I recently installed some AAR arms so naturally, I need to redo my alignment.


After scouring the web for weeks, reading grassroots articles on how to's...I started formulating a plan. I was willing to pay for tools and equipment but none of the existing products out there really did exactly what I wanted at the price point I wanted. Alignment specific camber gauges were expensive (>$100 manual bubble and >$200 digital) and did nothing but camber. Toe measuring devices (another $100) mostly just facilitated the old tape measure technique of measuring at the front and rear of the tire to get total toe across the axle, but I wanted individual wheels. The strings method didn't require much in the way of tools, but was a pita to setup.

So naturally, I thought I could do better, and even set out to make my own tools.

Here's what I came up with

Alignment frame to get accurate consistent measurements off the 3D faced wheel. Simple 1/4x1" aluminum stock, screws, and spacers. This tool couldn't be easier and more consistent to use. There's even a nice convenient knob at the bottom that lets me easily secure the tool to the wheel.


Checking camber... Cake. No need to buy an expensive camber specific bubble gauge. Just a general purpose digital level will do. I can even measure the level of the surface I'm working on first then subtract what the wheel camber reads to get true camber. Gauge read 88.2. 90 - 88.2 gives me a nice 1.8 degrees of camber here. Perfect.


Checking toe... The long aluminum L bracket sits on the ground and butts up against both wheels allowing me to easily see where the single tire sits is relative to the axle. Easy to gauge and set my 1/8" toe in via the little "drop down links".


It was a PITA to take off the wheels, adjust the camber and toe dials, remount the wheels, lower the car, roll the car back and forth to reset the suspension, take measurements, readjust and so on...but it was great to dial it in exactly as I wanted.
 

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wowee wow wow... very nice... +rep! what are you using to grab hold of the wheel's barrel? make sure the surface you are working on is level too :p ive made that mistake. adjusting the front is a PITA w/o it up in the air on its wheels. even tho it isnt a true double wishbone setup up front, camber, toe, and caster are all dependant to each other :( you get the toe all setup and then the camber is outta spec, once the camber is spec'd toe is slighter off... i wish i had a pit...
 

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nice job....i have some suggestions tho...your drop down links need to exteend the diameter of the tire or your 1/8" could actually be 1/4" total toe. now the most difficult part of rear wheel alignment. the dreaded thrust angle..i believe 4mm is the max here. if yoiu can find a straight edge that extends beyond the wheelbase(105.1") you can set your toe against your front wheels....and since you're doing a diy alignment i would suggest at some time to try zero toe at the back. this would minimize dog legging in case your thrust angle is off....+rep tho...
 

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Discussion Starter · #4 ·
About grabbing the wheels, the black hand nut adjusts the vertical upright on a sliding groove. The 3 points thrust against the rim and I can add a little tension via the hand nut.

nice job....i have some suggestions tho...your drop down links need to exteend the diameter of the tire or your 1/8" could actually be 1/4" total toe. now the most difficult part of rear wheel alignment. the dreaded thrust angle..i believe 4mm is the max here. if yoiu can find a straight edge that extends beyond the wheelbase(105.1") you can set your toe against your front wheels....and since you're doing a diy alignment i would suggest at some time to try zero toe at the back. this would minimize dog legging in case your thrust angle is off....+rep tho...
Good points. Your right that the drop links need to be the diameter of the tire. Since the drop points give me about 1/2 diameter, I just measured 1/16 to give me the 1/8". I wanted some toe in to help deflection under power which gives me a bit more stability.

I didn't see an adjustment for thrust angle? How do you even go about setting that? I was hoping that since my alignment was in good standing prior to the arms, that simple adjustments would get it where I needed.
 

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AWESOME write up man!!! now i don't have to let other people do my alignment and possibly mess it up...or at least i can save some good cash from doin it myself. +rep to you sir.
 

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You beat me to a write up. What i have seen that people do is level the car on wood shims. you could buy 4 Teflon cutting boards for the top so you can raise and lower car then the wheels will slide on the boards to settle the car. The other thing is that you are measuring relative toe there. That it one wheel to the next. To make sure your thrust angle is right you have to measure from a fixed point (middle) between the wheels.

Also how accurate are those digital angle gauges?
 

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Discussion Starter · #7 · (Edited)
I've also heard of getting 4x heavy metal plates and greasing them to get low cost slides. Or you could go to harbor freight and get those under wheel dollies for $40/pair.

Does anyone know how to adjust the thrust angles in the suspension? I didn't see any adjustments for it on the traction bar. Not that I need to though as I just measured against a common point on the frame and the wheels are where they need to be.

I didn't have a digital angle gauge. I would like an accurate way to give me degree numbers though but I think that gonna cost me more than it's worth.
 

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I think you are confusing thrust angles with pinion angles.

Check this guys page. It is a very good writeup on how to string your car. Time consuming, but crazy accurate.
 

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Discussion Starter · #9 ·
Hrmm... I just looked up thrust angles and it is what I thought. I'm confident the rear end (axle) is square with the chassis as I measured against the frame rail as well as measuring center line of the rear wheels to the front wheels. All square.

I don't even know where to adjust that in the first place as we dont' have axles...just the subframe which is hard mounted to the chassis w/o adjusters. Or is there something I'm not aware of?
 

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No thrust angle is really toe relative to the chassis. you can have 0 toe based on one wheel to the other, but relative to the chassis you can be pointed one way or the other. thats why they string from a fixed center to each wheel. If you Measured tire toe tire then tire to frame and got good reading then you should be fine.
 

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Discussion Starter · #11 · (Edited)
Ahh..I see where the confusion is.

Like I said in my first post, my method of setting toe did not depend on the toe of the other wheel, and was something I did not like about the tape measure method. I wanted toe relative to the chassis, not total toe on the axle.

If you refer to the first pic, I have an 8' straight edge butt up against the bottom of the tire. This allows me to set individual toe.
 

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Hey Paul would you care to align my car for a fee? For what ever reason fireston can't get mine into spec and im on prokits.
 

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Discussion Starter · #14 ·
I'll have to pass on the alignment as it's one of the things I really don't look forward to simply due to PITA it is to take on and off the wheels. The prof. have nice raised platforms where they can work from underneath the car.
 

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no worries just thought I'd ask. I'll just look for a firestone that can align my car within spec not just barely out. Kane told me that the Big O in poway aligned his car and he's alot lower then me.
 

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Discussion Starter · #16 ·
What is it that they can't align? They won't be able to bring the camber is spec which is expected. But the toe and caster should dead on. If they can't fix your toe right, then I would have reason to worry. Even with aggressive camber, you should be able to get descent tire life. Let me know if it's the toe they can't get right. I'll try to help where I can.
 

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My camber up front isnt to bad maybe slightly out of spec but the rear is maxed out at like 1.8 or something. I always ask that they set the cross camber at zero knowing the camber wont be in spec and to set the toe in slightly. The #'s come out fine I guess when finished but my toe goes out of wack fairly easily because when i look at the reports the toe is way off in the front. I don't know why that is. I do like to take corners some what aggressively at times but not all the time. Is our toe adjustment that sensative. I managed to get almost 30K out of my proxes 4's but only because i had the tired flipped due the camber/toe problems which i thought was pretty decent still.
 

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Discussion Starter · #18 ·
If you're getting 30k out of your proxes...you are just fine. Can't ask for more than that.

1.8 sounds spot on for the rear.
 

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yeah i guess your right but when my toe is off it eats up my inner wear like crazy. I'm going back to a 215 instead of a 225 to see if that helps. Any thoughts as to why my toe gets thrown off easily? Should I ask them to set the toe at zero instead of toe'd in a little?
 

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Discussion Starter · #20 ·
Hrmm...The IS keeps it's alignment very well. If it's getting thrown off (how do you know? by how much?), than a bushing is worn somewhere. But then again, 30k is exceptionally good tire life.
 
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